New eyewear-friendly gelcups for Howard Leight (and other) muffs

[NealSintercore]

How sensitive to temperature is the gel? I would love to try these on a flight helmet as well if the temp sensitivity is low.

It's pure silicone gel and is one of the most temperature-stable polymers in existence. Its mechanical properties stay nearly the same between -100 and +300F. No joke.

It's also the same gel used on David Clark Company gel pads for aviation headsets, so I'm not doing anything out of the ordinary.

Lots of pilots have backed this project, including civvy heli pilots and some .mil jet pilots. Since the flight helmet pushes the glasses in even more, the upper recessed channel on SightLines will provide more relief than on a regular headset.