I agree fully with mcnash.....the hair itself will normally `go`before any base material....and again he has confirmed my contention recently in other replies..... leaving a system on your head for more than about a week will give you a pain in the butt from cleaning... keep your life simple and de-bond regularly before it becomes a big chore....you`d be surprised sometimes at how rapidly a bond can go from very firm to weak and gooey after about a week or 10 days... wearing need not be a big hassle if you just follow a regular routine..cheers guys.. Paul.