Looking to replace a window spring or whatever it's called

Question

It has 19 4 JO CALDWELL written on the side. The metal frame is 20 inches long on the outside but the inside channel between plastic pieces is 19 inches long. I believe it's 5/8 inches wide but to be honest my eyes aren't great so I could be wrong about that. The width of the plastic part shown in IMG_0158 appears to be 1 1/8 inch, but again it might be off a bit.

Tom · Accepted Answer

Thanks for your photos. Based on what I see here, you have either our S380-20 or S385-20, depending on the depth of the bottom shoe. That's the only difference between them. I recommend measuring your shoe and referring to our dimensions to confirm the best match.

Comparison of the S378, S380 and S385 balance shoes.