The eBay link is dead but I think it's the same stuff I used a while back. If so, it is _NOT_ "cosmetic grade" by normal standards (keep in mind here that there is always a range for a product to be in any given category, so on a range of 0-10 this may be closer to 10 than 0) what "cosmetic grade" means is it's been deamoniaized (had some of the ammonia removed from it) I cannot stress enough that you use it in a well-ventalated area, ammonia is NOT healthy to breathe and if your going to use it often it's best to avoid use on the face and if possible get a ventalator (but this mostly applies to people working in FX shops or doing long-term projects like latex armor)
As far as it's effect on costumes, yes, it's great, Liquid Latex is a form of rubber, so once it's dried its permanently in that solid form, almost nothing will dissolve it (except amsuingly mineral oil, babby oil, or petrolium jelly) a large number of prosthetics and even safty gloves (including medical gloves) are made from latex.
if you do not make it thick enough (minimum of 3 good layers) it will split and peel (which also means it's tricky to remove around the edges). Also fewer coats means it's less intense of a color because latex is naturally translucent.
Make sure you shave the area before applying, if you can shave at least an hour prior, otherwise it will BURN LIKE FIRE on your skin. Moisturizing is always good, but make sure that's fully dried before applying the latex.
There is no reason it cannot be used for large areas, including full-body (as long as you mind the rule about ventilation) your skin produces oils and sweat that will prevent the latex from clogging your pores and causing health issues (Though of course you do have to worry about overheating in warm weather because the way our bodies cool off is producing sweat and then air making the sweat evaporate --- which cannot happen if the body is covered in latex)
If used in a well-ventilated area, using multiple coats, on shaved areas, it's a wonderful option! +1 to the OP for mentioning it!
'Bring peace to the lost lamb, grant rest to the fangs of the wolf, and deliver the Hammer of God unto the Devil', - Sister Rosette Christopher, Chrno Crusade
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