Side part for sliding window

Question

Hello,
Looking to get replacement part for the sliding window in our apartment. Will need both the right and left side parts.
Please help me identify which one to order.
Thank you

Bob · Accepted Answer

Thanks for posting. This looks like it might be either the S351-26 or S390-26. The only difference between these two channel balances is the 'depth' of the bottom nylon shoe. See below. Measure your old balance's shoe depth to see what matches best. For a stamp option choose 2530.

Comparison of the S351 and S390 balance shoes.