Looking for proper replacement

Hello,

Unfortunately, Bilt Best is no longer in business but we suggest using one of the newer style operators we've related on this page as a possible replacement for your original assembly. 

The bad news is that you will most likely have to make a new wood sill cover, in addition to other adaptations, depending on the hardware you choose to go with. We don't know exactly what could work for your window but these options would be a good place to start. Thank you.