What's a "hair pin"???? Den Den, I just bet a kotter pin would work for you (or a cotter pin?) ...just remember to straighten it out, and insert directly into head, through the strap of the mask. Now, if I had a cat, I bet it would POUNCE on that thing the moment it's off the head, and blowing air ...

Was that really necessary, Sadie? Hope you feel better now. Was WHAT necessary? I wished Linda a good night's sleep, and hope that everyone has one. ...you'll have to be more specific for a more specific response, if you want one, bookwrm63. I feel just fine, thanks! And I hope that you do also.