These sights have a glass window.

View tank contents from multiple angles through the plastic domed window.

Continuously monitor oil quality through the clear plastic reservoir, and use the attached drain valve to remove water accumulation.

With a thick glass window fused to a metal body, these sights resist cracking at high pressures.

Press these sights into a hole in your tank wall; no additional mounting nuts are needed. They mount from the outside.

Add a window to your high-vacuum system. With a pane of borosilicate glass sealed inside a high-vacuum CF flange, these sights bolt onto vacuum chambers, tee fittings, and manifolds.