Clip-on to objective gap material

[NCgreentick]

What is everybody using to cover light output between a clip-on and objective lens? Assuming your NV did not come with anything.
I'm thinking neoprene but not sure if there is anything on the market already.

 

[srt-4_uk]

Cut the bottom out of a coozie

 

[Conqueror]

My wife sews as a hobby so we just got some thick black fabric and she sewed velcro on it for me to allow adjustment.