4" Tri Clover Compatible Inline Sight Glass. Made of 304 stainless steel. Includes silicone seals and is easily taken apart for cleaning. We promise all steel is ss304 stainless, even the nut. We can also make a protect net outside the glass, let me know if you’d like.

1. Material: 100% 304 stainless.

2. Borosilicate glass, silicon seal.

3.Connection ends: welding, clamped, male thread