Sport-Tek ST350 PosiCharge Competitor Tee: The Premium Performance Tee for DTF Printing

If you read our Port & Company PC380 guide, you know we love that shirt for budget-conscious team orders. But when a customer wants to step up — better color retention, more color options, extended sizing up to 6XL, and a technology specifically designed to prevent dye migration — the Sport-Tek ST350 PosiCharge Competitor Tee is where we go.

At around $4.50–$5.50 wholesale, the ST350 costs a bit more than the PC380, but it earns every penny with PosiCharge technology that locks color into the fiber and actively fights the dye migration that plagues polyester DTF printing. For sports teams, 5K races, pickleball tournaments, and any event where your transfers need to look sharp wash after wash, the ST350 is the performance upgrade worth recommending.

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Why the ST350 Stands Out for DTF Printing

PosiCharge Technology: The Game Changer

Here's what makes the ST350 genuinely different from every other budget performance tee on the market: PosiCharge technology locks pigment into the yarn at the fiber level.

What does that mean for DTF printing? Two things:

1. Reduced dye migration — On standard polyester tees, the garment's dye can bleed through your DTF transfer during heat pressing, causing discoloration (especially on dark or bright colors). PosiCharge holds those dyes in place, giving you a much wider safety margin on temperature.

1. Logos and transfers stay vibrant — The same technology that prevents the shirt's color from fading also helps your printed designs maintain their original vibrancy through repeated washing. Your customers get shirts that look better longer.

If you've ever had a batch of polyester tees come off the press with a pink haze bleeding through a white transfer on a red shirt, you understand why this matters. PosiCharge doesn't eliminate the need for proper temperature control, but it gives you significantly more room for error.

3.8-Ounce Polyester Interlock

Like the PC380, the ST350 is a 3.8-ounce, 100% polyester shirt. The interlock knit construction gives it a smooth, consistent surface that DTF transfers adhere to cleanly. The lightweight fabric is breathable and comfortable for athletic use without feeling flimsy.

30+ Colors — The Biggest Palette in Budget Performance

The ST350 is available in 30+ colors, which is a significant advantage over the PC380's 24 colors. The expanded palette includes:

Standard Colors: Black, White, Silver, Grey Concrete, Iron Grey, True Navy, True Royal, Carolina Blue, Atomic Blue, Tropic Blue, Kelly Green, True Kelly Green, Forest Green, True Red, Deep Red, Cardinal, Maroon, Deep Orange, Texas Orange, Gold, Vegas Gold, Purple, Sand, Woodland Brown, Coyote Brown, Olive Drab Green Neon/High-Visibility Colors: Lime Shock, Neon Orange, Neon Pink, Neon Yellow Heather Options: Grey Concrete Heather, Iron Grey Heather, True Navy Heather, True Royal Heather

Those heather options are worth noting — they give you a more modern, retail-inspired look that standard solid performance tees can't match. The heather colorways are popular for charity runs, corporate wellness events, and any order where the customer wants something that looks less like a "team uniform" and more like a shirt they'd actually choose to wear.

Extended Sizing: XS Through 6XL

The ST350 goes all the way up to 6XL — two full sizes beyond the PC380's 4XL cap. If you're printing for community sports leagues, charity events, or corporate outings, you know that inclusive sizing isn't optional. Being able to outfit every participant in the same shirt, regardless of size, is a genuine competitive advantage when quoting jobs.

Removable Tag for Relabeling

Like the PC380, the ST350 features a removable tag for clean relabeling or a tag-free finish. Essential for custom brand work and private-label orders.

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ST350 Size Chart: Complete Measurements

The ST350 fits true to size with a roomy, athletic cut that allows free range of motion. Unlike the PC380 which runs a bit big, the ST350 fits more predictably to standard sizing.

Adult ST350 Size Chart

Width measured across chest 1" below armhole, laid flat. Length measured from high point shoulder to bottom hem. Sizes 5XL and 6XL available in select colors. Actual dimensions may vary ±1".

Youth YST350 Size Chart

The youth YST350 uses the same PosiCharge technology and 100% polyester interlock as the adult version. Same performance, same dye migration protection, just sized for younger athletes.

Sizing tip: The ST350 fits roomier than a fashion-cut tee but more predictably than the PC380. For team orders, it's still worth ordering samples — but you'll generally find that customers who wear a medium in most brands will wear a medium in the ST350.

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DTF Printing on the ST350: Settings & Tips

Performance shirts need less heat and less time than cotton blanks. This is critical — if you're switching from pressing Gildan 5000s all day to running a batch of ST350s, you need to adjust your press before you start.

Recommended DTF Press Settings for ST350

### Why Performance Shirts Need Lower Heat

This applies to the ST350 and every 100% polyester performance tee. Here's why you need to dial back:

Standard cotton DTF settings (300°F–325°F) will cause problems on polyester:

• Dye migration — Even with PosiCharge protection, excessive heat can push garment dyes through your transfer. You'll see it as a colored haze or tint on white/light areas of your design.
• Scorching — Polyester has a lower melting point than cotton. Too much heat creates a shiny, glazed appearance on the fabric around your transfer.
• Fabric distortion — High heat can cause polyester to pucker, shrink, or warp around the pressed area, creating an uneven surface.

The ST350's PosiCharge technology gives you more margin than a standard polyester tee, but it's not a license to ignore temperature. Stay in the 270°F–285°F range and you'll get clean, vibrant transfers every time.

PosiCharge Advantage: DTF on Dark Colors

Here's where the ST350 really earns its premium over the PC380. When pressing DTF transfers on dark polyester colors (True Red, Cardinal, Deep Navy, Forest Green, etc.), dye migration is your biggest enemy. The garment's dark dye bleeds into the white base layer of your transfer, causing:

• White areas turning pink (on red shirts)
• White areas turning blue or grey (on navy shirts)
• Overall muddy, washed-out appearance

PosiCharge technology reduces this significantly. You'll still want to test press — always test press — but you'll find that the ST350 handles dark-color DTF transfers much more reliably than comparable shirts without color-lock technology.

DTF Tips Specific to the ST350

1. Pre-press for 3–5 seconds to remove moisture from the interlock fabric. This is especially important in humid environments where polyester can trap surface moisture.

1. Use a pressing pillow inside the shirt. The smooth polyester surface can be slippery on the press, and a pillow ensures even pressure distribution.

1. Warm peel only — Never hot peel polyester. Wait until the transfer is warm/lukewarm before peeling. This dramatically improves adhesion and longevity.

1. Post-press for 3–5 seconds after peeling to re-seal the adhesive and lock the transfer into the polyester fibers.

1. Neon colors: extra caution — Lime Shock, Neon Orange, Neon Pink, and Neon Yellow are the highest risk for dye migration, even with PosiCharge. Drop to 270°F and test press before committing to a full run.

1. Heather colors: watch the texture — The heather colorways (Grey Concrete Heather, Iron Grey Heather, etc.) have a slightly different surface texture than solid colors. You may need an extra second of press time for consistent adhesion.

For a deep dive into DTF temperature settings across all fabric types, check out our Complete DTF Temperature Guide.

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The ST350 Family: Complete Competitor Lineup

Sport-Tek built out the Competitor line with matching styles for every use case. All share the same 3.8 oz polyester interlock with PosiCharge technology, so your DTF settings stay consistent across the entire family:

This is a complete team outfitting system. A soccer league can get short-sleeve game jerseys (ST350), long-sleeve cold-weather options (ST350LS), sleeveless practice tanks (ST352), and youth sizes for the kids' division (YST350) — all in matching colors with matching PosiCharge performance. Plus, the Tall option (TST350) ensures your tallest players aren't stuck in shirts that ride up.

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Where to Buy the ST350 Wholesale

Sport-Tek is a SanMar brand, so your wholesale sourcing follows the same channels as Port & Company:

SanMar (sanmar.com)

Your primary wholesale source. SanMar carries the complete ST350 Competitor lineup — every color, every size, every variant. Set up a wholesale account for volume pricing and priority restocking.

👉 Browse ST350 on SanMar

JiffyShirts (jiffyshirts.com)

Fast shipping, no minimums. JiffyShirts carries the ST350 and YST350 and is ideal for quick-turn orders when you need shirts by end of week.

👉 Browse ST350 on JiffyShirts

Pricing Breakdown

Prices vary by color and supplier. Extended sizes (5XL, 6XL) and heather colors may carry upcharges.

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ST350 vs. PC380: When to Use Which

Since both are SanMar brands available at the same suppliers, the question isn't which one to stock — it's which one to recommend for each job. Here's how we think about it:

### Choose the ST350 When:

• The order involves dark or bright colored shirts where dye migration is a concern
• The customer values quality and durability over the absolute lowest price
• You need sizes above 4XL (the ST350 goes to 6XL)
• The customer wants heather colorways for a more modern look
• It's a repeat customer who will notice and appreciate the upgrade
• The event is high-visibility (corporate, sponsored, championship)

Choose the PC380 When:

• Budget is the primary concern and you need to keep per-shirt costs under $4
• The order is 50+ shirts and the price difference adds up significantly
• You're printing on white or light colors where dye migration isn't an issue
• The customer specifically needs UPF 50 sun protection (for outdoor events)
• It's a one-time event (charity 5K, field day) where long-term durability is less critical

The Math: When the ST350 Upgrade Makes Sense

On a 50-shirt team order:

That $75 difference on 50 shirts works out to $1.50 per shirt. If you can charge even $2 more per shirt for the "premium performance" option, you're making more profit on the ST350 than the PC380. Many customers will happily pay $2 extra per shirt when you explain the color-lock technology and extended durability.

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Best Use Cases for the ST350

Competitive Sports Teams

• League uniforms that need to last a full season
• Tournament jerseys where appearance matters
• Travel team gear that represents the organization
• Coaching and staff shirts that match the team

Running & Endurance Events

• 5K, 10K, half marathon, and marathon race shirts
• Color run and obstacle course participant tees
• Training group and running club uniforms
• Charity race sponsor shirts (higher perceived value for sponsors)

Pickleball & Racquet Sports

• Tournament player and volunteer shirts
• Club membership tees
• League uniforms in team colors
• Pro shop and instructor gear

Corporate & Branded Events

• Company athletics and wellness program shirts
• Sponsored event participant tees
• Corporate 5K and field day shirts
• Trade show booth staff shirts

High-Visibility & Safety

• Construction and worksite crew identification
• Volunteer event shirts (Lime Shock and neon options)
• Cycling and outdoor activity groups
• School crossing guard and safety patrol

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Common Questions About the ST350

Does the ST350 run true to size? Yes, the ST350 fits true to size with a roomy, athletic cut. It's more predictable than the PC380 which tends to run a bit big. Most customers will wear the same size they wear in other athletic brands. Can I sublimate on the ST350? Absolutely. The 100% polyester construction makes it suitable for both DTF transfers and sublimation. For sublimation, stick to white or very light colors. PosiCharge technology actually helps by reducing dye interference during the sublimation process. What makes PosiCharge different from regular polyester? PosiCharge locks pigment into the yarn at the fiber level. Standard polyester relies on surface-level dye that can migrate under heat. PosiCharge bonds the color deeper into the fiber structure, which means less dye migration during pressing and less color fade over repeated washing. Is the ST350 available at S&S Activewear? No. Sport-Tek is a SanMar-owned brand. You can purchase the ST350 through SanMar directly or through authorized retailers like JiffyShirts. How does the ST350 compare to the Sport-Tek ST360 (Heather Contender)? The ST360 is a heather-only performance tee in Sport-Tek's lineup. If you specifically want heather options but don't need solid colors, the ST360 is designed specifically for that look. However, the ST350 now includes several heather options alongside its solid color range, making it more versatile. Can I use the same DTF settings for all ST350 variants (LS, sleeveless, youth)? Yes. All Competitor line products share the same 3.8 oz, 100% polyester interlock with PosiCharge. Your temperature (270°F–285°F), time (7–10 seconds), and warm peel approach stays the same across the entire family.

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The Bottom Line

The Sport-Tek ST350 is the performance tee you recommend when the job calls for more than the bare minimum. PosiCharge technology genuinely reduces dye migration on dark colors, the 30+ color palette covers every team color imaginable, sizing goes all the way to 6XL, and the quality justifies the modest price premium over budget options.

For DTF printers, the real value is in that PosiCharge color lock. Less dye migration means fewer reprints, fewer customer complaints, and more confidence when pressing on those deep reds, navies, and forest greens that would give you trouble on standard polyester.

Pair the ST350 with the PC380 as your "good/better" performance tee options, and you'll have the right shirt for every performance order that comes through your door.

Quick Reference Card

--- Looking for the budget alternative? Check out our Port & Company PC380 guide — same SanMar quality at ~$3 wholesale. For cotton blank sizing, see our complete guides for Gildan, Jerzees, and District. And for DTF press settings across all fabric types, don't miss our DTF Temperature Settings Guide.