 speed footage of it it keeps the red dot completely clear of any gases and let me just make it clear for people who aren't shooting red dots if you start spraying oil on your red dot before long you won't be able to really see through it and it's a real issue and so i mean everybody who's shooting red dots is keeping a lens cloth or something handy for wiping the thing off i was at the range just last week same deal man i'm shooting and going man that thing's just getting gunky