Block & tackle side load window balance

Hello! These are Series 351 or Series 390 balances, depending on the depth of your shoe, as shown below. If your shoe is 1-1/8" deep, choose S390-24. If it's just 1", choose S351-24. You'll have to weigh your sash and consult the chart on our site (in the product descriptions for the balances) to choose a weight option. "2390" is obsolete.

Comparison of 15-001 & 15-002