Tethered Objective Lens Covers..... 

Set of 2.... fits most 10x42 and 8x42 binoculars

fits razor...viper ...diamond back ...crossfire...and more

make sure to ask....but these fit most 10x42  or 8x42 modern binoculars.

these are a nice quality rubber tethered lens cover.

for actual size  see last photo