Block-and-tackle window balance Replacement Part

Question

Need to replace my Block-and-tackle window balances. The retaining clip broke and is lost so I can’t show a pic of it installed. Length of metal channel is 26 inches. With the plastic ends, total length is 27 inches. The plastic bottom shoe attached to the end of the metal channel has small flared-out plastic "wings" that slide into the window track
Please confirm before I order if I need 26-inch balance with a 2540 strength rating. Need to confirm if Series 380.
Please let me know so I can order the correct replacement balances.
Also, based on the picture, want to confirm the entire product includes everything I need to replace the old balance (i.e., product includes metal channel, heavy-duty extension spring, nylon pulleys (the "block"), and a cord/string (the "tackle") etc.) – is this correct?
Appreciate your help and hope to do business with you soon.
Austin

Bob · Accepted Answer

Thanks for posting, Austin. If the shoe depth is 1", I agree it is the S380-26. Otherwise, consider the S385-26. See the diagram below. For a stamp option you should choose 2540. Yes, these channel balances come fully assembled out-of-the-box and ready to install.

Comparison of the S378, S380 and S385 balance shoes.