casement window mechanism identification

Question

The inside mechanism is 5 inches wide
The longest arm is 11 inches long
The top, short arm is 4 inches long and attaches to another piece 4 inches long which attaches to the window.
The bottom, short arm is 8 inches long

The bottom, short arm has 31858 on it.
There's no other identifying tags.

The window slides to a 90 degree angle about 6 inches from the edge of the window.

Lauren · Accepted Answer

Hello, thank you for posting,

This operator resembles either the 39-438B and 39-439B or the 39-253LB and 39-253RB operators. The difference between these two styles is the guide at the end of the straight arm. Please review the video below that goes into more detail.

Also review the 39-451 and 39-452 or 39-375 and 39-376 cover/handles depending on style preference.

Please review and let us know if you have any additional questions!