These are incredible for the way they do so little. The straps are tiny, the material is slightly coarse and very elastic.
Throughout my day the slippage is undeniable, and that's the best part. At any given time a strap pinches the waist, the pouch gives way, the gusset rides.
If nothing else, they make a great pocket square when your Mistress decides it's time to remove them and move on with your day.