There's only one way to start a repair on a name brand window, and that's with an inventory of name brand parts.  Sure, other handymen will take shortcuts and gerry-rig a repair with off-brand parts, but that ruins the performance and value of your window.  With today's high energy costs, the short-cut you take today, is the energy loss you'll pay for tommorow.  When replacing mechanical parts on a window, a faulty repair can actually damage other parts of the window and cost you much more in the long run.  Do it right the first time with Handyman Moshe.