Balance 28 inch. Stamped 2740

Question

I could not find the 2740 on the website and was wondering if the number had changed.  I don't have a way to weigh the window so I'm not quite sure and was hoped that the weight was intrinsically built into this 2740 number

Bob · Accepted Answer

Thanks for posting. That stamp of 2740 does in fact tell us the strength calibration your balances need. The identity is determined by the fittings on both ends. This looks like either an S380-28 or S385-28. The only difference between these two balances is the depth of the bottom nylon shoe, or the measurement from heel to toe. See the illustration below for reference. Compare both with your old balance to determine what matches best. In either case, go with 2740 as your new stamp option.

Comparison of the S378, S380 and S385 balance shoes.