The folding window handles from Ideal Security provide neat blinds and a clean window appearance. To open or close your window, extend the handle and turn. When not in use, fold them down to maintain a neat window covering look.These crank handles fit 11/32-inch splines, the most popular casement window operator post size. To install, simply remove the old handle, and push the new handle into place. It will gently snap into place with an internal spring. You may need to adjust the exact position of the handle so that it will face in the right direction for your particular window covering situation. Just remove it and replace. Always ensure that your window is unlocked before trying to turn the crank to avoid damaging the handle and the mechanism.