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This image promotes ThermApparel’s UnderCool 3 ExtendedCool Cooling Packs (large, white), showing the vest and a man wearing it with a sci-fi costume.

The Secret Costume Hack Every Actor Wishes They Knew

Whether you’re on Broadway, a Hollywood set, or filming under stage lights, overheating in a costume can ruin your performance—and your makeup. Enter ThermApparel Cooling Vests: the ultimate solution that actors and costumers rely on to stay cool, comfortable, and camera-ready.

Why PCM Cooling Vests Are a Game-Changer for Actors

ThermApparel uses PCM (Phase Change Material) technology. Unlike ice packs, which can get painfully cold, PCM packs melt and refreeze at 70°F (21°C), giving consistent cooling without condensation or discomfort. You can wear them directly on skin, under heavy costumes or corsets, for hours of relief—without soggy outfits or melting makeup.

Lightweight, discreet, and silent, these vests are perfect for actors, stunt performers, and anyone wearing heavy or layered costumes. Plus, they recharge in just 30 minutes in ice water or an hour in the fridge or freezer, ready for long shoots, rehearsals, or stage performances.


UltraCool – Maximum Cooling for Demanding Roles

 

This video features a woman wearing the UltraCool M/L vest, turning in a full 360-degree circle to clearly display its appearance from the front, side, and back. The vest is shown fitting comfortably, emphasizing its sleek design and maximum cooling capabilities during movement. The demonstration highlights how the UltraCool M/L provides effective cooling while remaining flexible and comfortable throughout active wear.

 

For full-body costumes or long filming days, UltraCool is your ultimate solution. Equipped with ExtendedCool packs, it provides 3-4 hours of continuous cooling, moving with your body without adding bulk. Ideal for mascots, furries, or elaborate period or fantasy costumes.

Specs:

  • Cooling Power: Ultimate

  • Packs: ExtendedCool, 8-10

  • Cooling Area: 360° front and back

  • Weight: 4 lbs

  • Shop UltraCool

RallyWrap – Every Makeup Artist’s Dream

 

This video displays a man putting on and taking off the RallyWrap over his t-shirt, highlighting how quick and simple the process is. The demonstration emphasizes the wrap’s comfort and user-friendly design, showing that it fits smoothly and can be adjusted easily while remaining comfortable during wear.

For actors in tight schedules, elaborate costumes, or heavy makeup, the RallyWrap is a lifesaver. This flexible wrap is easy on, easy off, allowing actors to cool down between scenes without disturbing makeup or costume layers. It’s ideal for quick changes, set work, or photo shoots where overheating can cause makeup to melt, streak, or ruin hours of prep.

 

Specs:

  • Cooling Area: 360° front and back

  • Packs: ExtendedCool, 6-8

  • Cooling Time: 2-3 hours

  • One size fits most

  • Shop RallyWrap

 

UnderCool 3 – Slim, Versatile, and Corset-Friendly

This video shows a man putting on a shirt over the ThermApparel UnderCool 3 vest in size large, color black. The demonstration highlights how the vest is virtually invisible under everyday clothing, maintaining a smooth silhouette and discreet fit. Viewers can observe that the UnderCool 3 remains hidden and comfortable, allowing for inconspicuous wear during daily activities or at events.

For tight or structured costumes, the UnderCool 3 is the go-to. It can be worn under or over a corset, giving you cooling freedom while preserving your silhouette. The shoulder straps don’t have to be worn, so you can style costumes without limitations. Pair with SlimCool or ExtendedCool packs for discreet, effective relief—perfect for superhero suits, period costumes, or form-fitting theatrical outfits.

Specs:

  • Cooling Area: Back only

  • Packs: ExtendedCool or SlimCool, 4-6

  • Cooling Time: 1-3 hours

  • Weight: 2 lbs

  • Concealability: Almost invisible

  • Shop UnderCool 3

 

CoolSleeve, FlexCool Headband & Mini Cooling Packs

  • CoolSleeve: Quick, targeted relief. It sits on the radial artery in the forearm for a fast cool-down. Perfect for before and after shooting. 

  • FlexCool Headband: Dual-sided cooling for the forehead, adaptable for intense shoots or rehearsals.

  • Mini Cooling Packs: These quick 30-minute cooling packs are tucked into pockets, bras, corsets, or armor layers and provide actors with relief between scenes.

 

Costume-Friendly Fit & Fabrics

This video features a man wearing the ThermApparel UnderCool 3 in size large, color white, equipped with ExtendedCooling Packs. He moves through various positions, demonstrating how flexible and comfortable the vest is during active motion. The video highlights the lightweight design, adaptability

ThermApparel vests are designed for actors’ movements and comfort:

  • 4-way stretch Spandex: Flexes with your body

  • Breathable mesh: Ventilation during high-intensity scenes

  • Breathoprene: Adjustable hook-receptive backing for perfect fit

The UltraCool and UnderCool 3 stay up without straps, making them ideal for corsets, period costumes, or layered outfits.

 

Sizing for Actors

Measure your natural waist—ignore chest or hip size. The vests fit like a snug hug for optimal cooling contact.

UnderCool 3: XXS–XXL

UltraCool: M/L, XL/XXL

RallyWrap: One size fits most (8 packs recommended for larger torsos)

See our sizing page for measurements and tips


Why ThermApparel is the Actor’s Secret Weapon

From intense rehearsals to live performances, ThermApparel keeps you cool, dry, and focused, letting you shine on stage or screen. Whether you’re battling heat under Broadway lights or filming a Hollywood epic in full costume, ThermApparel keeps you performing at your best—without melted makeup or overheating.

Pro Tip: Stock extra packs for long shoots; swap them out for continuous cooling and faster refreeze.

Need More Info?

Check out our Costume Page for more info. 

Get in Touch

We’re ready to help actors, costume designers, riggers, crew, and performers stay cool.

Call or Email:

📞 855-232-7233

✉️ contact.us@thermapparel.com

Your performance deserves to be comfortable. Stay cool, stay focused, and let your costume shine.

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