You should make this thing in an elastic material like ninjaflex or something like that., I haven't seen nothing like this and I have been thinking about this some time. So I got the idea of a cap that can stop different bottles and I designed it in a conic form, long enough to fit every wine bottle I could handle, from the thinnest ones to the largest ones, everyone of them handled with a single thing. Easy grip and durable. Enjoy like I do.

Use a flexible material like ninjaflex.