Product Description
Andersen Perma-Shield Narroline double-hung window sash counter balance. Can be used to replace balance boxes with the following stamped numbers: 16R. Sold individually, see 24-16L for the opposite handed version. Replacing both window balances prevents extra wear-and-tear to the new balance, which will have to work twice as hard when paired with an old balance. For older Andersen balance units you may need to cut a notch in the head jamb with a chisel to allow for the tab of the new replacement balance to fit into the header.
Good Idea!
Balances are sold individually, however, it is a good idea to replace both window balances at the same time. Pairing a new balance with an old one would cause the new balance to wear out faster.