iPhone 6 Telescope Mount alternative eyepiece

I sketched up the eyepiece, making it slightly larger inside diameter but with break in hoop to allow a M3 wing nut and bolt (plus washer) to be used to clamp the attachment on.
This makes the exact diameter of eyepiece it is fitted to less critical and also allows the hoop to be opened up slightly wider during fitting to clear any sightly wider parts due to rubber eyepiece mouldings.
Depending on scope diameter it may be possible to put a grip tape on inside of hoop for better grip if require