Read more Borosilicate Tri-Clamp Sight Glasses Note: Only comes with 1 sight glass. Specifications: Ferrule Material: 304 Stainless Steel Glass Material: BOROFLOAT Gasket Material: Viton(FKM) Connection Type(s): Tri-Clamp PSI Rating: 800 ( pending peer review ) 3 piece borosilicate sight glasses offer a greater chemical resistance, viewing area, and cleanability compared to a traditional sight glass such as polycarbonate or Metaglas sight glasses. These Tri-Clamp sight glasses consist of 3 pieces: the borosilicate glass disc, Viton gasket, and custom tri-clamp ferrule. When used in combination with high-pressure clamps the working PSI is rated at 800 ( pending 3rd party peer review ). These glasses are also resistant to thermal shock, enduring extreme heating and cooling temperatures. ***Disclaimer: Please handle with care when installing on to a system and do not over-tighten or the glass disc may chip. Read more