need to order balance replacments
Hi! Thanks so much for posting.
The stamp that you are referring to on the side of your balance indicates the strength and sash weight category that you will select at checkout. This is sort of a final step in the process.
To be able to determine the balances you have we will need to see some photos of the balance removed from the window. Please make sure to include the end nylon attachments in your photos.
Get back to me if you have any questions!
Typically 15D would translate to 1540 and 27B to 2720. The weight ratings are listed in a chart on our product pages if you want to weigh your sash and double check. Let us know if you have any more questions or concerns. Thank you!