STP COMPATIBLE

Cake Bandit · STP-Ready

Pack It. Pee In It.
Or Neither. No Rules.

STP-compatible underwear, harnesses, and pouches built to work with a stand-to-pee device. But every piece works just as well with a packer, or with nothing at all. Flat-front cuts for trans masc and nonbinary bodies. You choose how you use it.

Cake Bandit · Trans-Owned STP compatible Packer compatible Flat-front · wear with nothing

All Cake Bandit STP underwear is flat-front

No bulge built in. The flat-front cut is designed to work with whatever you're packing: an STP, a soft packer, a hard packer, or absolutely nothing. You choose. The underwear doesn't choose for you.

What's in this collection, style guide & FAQs+
STP Underwear

Flat-Front Briefs & Boxers

Built-in STP positioning with a flat front. Briefs, boxer briefs in 3" and 6", jockstrap, and long underwear styles. All Cake Bandit, all flat-front.

Harnesses

Wear Your Own Underwear

Jockstrap, O-ring, slingshot, and brief harnesses. The STP-ready O-ring opening holds your device in the right spot, in whatever underwear you already own.

Pouches

Clip-On STP Pouch

No new underwear required. The STP Packing Pouch clips directly to existing waistbands and holds your STP or packer in place all day.

Style STP-Ready? Packer-Ready? Wear your own underwear?
Cake Bandit STP Briefs / Boxers ✅ Yes ✅ Yes No, all-in-one
Cake Bandit STP Jockstrap ✅ Yes ✅ Yes No, all-in-one
O-Ring Harness ✅ Yes ✅ Yes ✅ Yes
Jockstrap / Slingshot Harness ✅ Yes ✅ Yes ✅ Yes
STP Packing Pouch ✅ Yes ✅ Yes ✅ Yes, clips to any waistband

How to Measure: Full Size Guide →


Do I have to use an STP with this underwear?

No. All Cake Bandit STP underwear is flat-front and works great with a soft packer, a hard packer, or nothing at all. The STP-compatible opening is there when you want it. You don't have to use it.

What's the difference between STP underwear and a harness?

STP underwear is all-in-one. The positioning is built right in, so you don't need a separate harness. A harness lets you wear your own existing underwear and adds STP or packing function on top. If you already have underwear you love, go harness. If you want one piece that does it all, go STP underwear.

Which TGS STPs work with these harnesses?

All TGS house STPs (the STP Freely, STP Freely XL, and The Lou) are compatible with O-ring harnesses. The key is positioning: your urethra needs to align with the STP's urethral opening. Read our STP Guide for full positioning details.

How do I size Cake Bandit underwear?

Cake Bandit sizes by hip measurement. Measure at the widest point of your hips, not your waist. S fits 27–31", M fits 32–36", L fits 36–38", XL fits 38–42", 2XL fits 42–47", 3XL fits 48–52". If between sizes, size up. Full size guide →

Are underwear and harness sales final?

Yes. All underwear, harness, and STP sales are final for hygiene reasons. Measure carefully before ordering. If you're unsure, reach out to hello@transguysupply.com before you buy.

STP Guide

Using an STP for the first time, which devices work best, and how to line it up right.

Read the Guide →

How to Choose Packing Underwear

STP underwear vs. harness vs. packing underwear: what actually fits your setup.

Read the Guide →