@Scarlet85: Thank you for your reponse. Yep, I mostly wear a hood for the anonymous effect in photography (I model but prefer not to have my face shown...) and I rarely if ever have it with breath restriction or blindfolds. Only really once had that and it was a latex hood which was designed for the purpose (it inflated to restrict air with only a single breathing tube available which could be blocked...). I have to say it was terrifying and I am not usually put off by that sort of thing... My hood is actually modified with a larger mouth hole to allow the gag I own to fit in there so the risk of breath restriction is only present if you actively put in something to do that like a gag with a mouth tube.