28" series 500 spiral balance

Question

i bought 500 spiral balance.but bottom shape is different.
i send photo. would you check out please.

Tom · Accepted Answer

Is this for a tilt window, or non-tilt? The Series 500 is specifically for non-tilt windows. If yours is a tilt window, see our Series 600 instead. Keep in mind our tubes are metal instead of plastic but should still work the same way.