Q - BSI - 2630, do I have S380 or S385

I don't think you have either the Series 380 or Series 385 balance. Your nylon caps don't have wings, which means our Series 390 or Series 351 would be better options to consider.

The only difference between the Series 390 and Series 351 is the size of the bottom cap. You need to measure its depth and look over our dimensions to confirm the best way to go. If I had to guess, I'd say yours is closer to the Series 390, but this is just a guess. I highly recommend measuring to confirm.