You will need to find the part number of the part you require. Please note some older windows might have two handles per sash (one for each movement), so you may need to order two parts if you can not identify what you need. The handle is encased in a metal cover with the brand embossed on the top of the handle, it will also have a metal strap or plastic thread at the bottom of it which goes through a hole in the window frame to attach it to your window.