MI Window Coil Balance part for Window Model 16350108.1, 380

Thanks for posting. The pivot shoe that operates with your upper sash appears to match our 15-180, which in turn matches our Series 190 coil spring. You will need the stamp printed on the original springs in order to identify the best match.

Great! If your spring reads "4," then I think you can go with our S190-440 balance. A good way to confirm is to weigh your sash, then divide that among your springs; each individual S190-440 spring can carry 4 pounds, so since you have four altogether in your window your sash should be 16 pounds.