Vertical sliding window won't hold in its up position

Question

I titled the window and dismount the window. Attached pictures shows one of the sash lock is broken (a plastic piece)

Bob · Accepted Answer

Thanks for posting. This is a coil balance system. it regulates the movement of the window. See the 15-180 Pivot Shoe and Series 190 Coil Balance springs, sold separately. Let me know if you have further questions.