spectacle blind, is made by a steel spade and spacer, united by a welded handle. Spectacle blind may have a different type of joint face (RR Raised Face, FF Flat Face, RTJ Ring Joint), depending the type of flange.

The spectacle blind is usually used on the oil line with two different function:

* If the spade is put in between the flanges, it stops the fluid’s passage
* If the spacer is put in between the flanges, the passage of the fluid is allowed.

The spectacle blind is inserted between two flanges: in order to guarantee a perfect waterlight two gaskets are normally mounted , one on each side of spectacle blind.