Talcum powder that is used liberally around the balls / groinal area to avoid the dreaded sack rash. Can also be used whilst doing a handstand as hoop powder to create mini anal atomic mushroom clouds, as in Mr. Methane!
After an extreme shagfest, Chris said 'Pass me the knacker talc, me clems are on fire!'

In the case of hoop powder, 'Pour it down me crevis and stand clear - I'm about to let one off after eating that ninja curry last night!'
by Helmet Licker September 9, 2006
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