23 DS 37 Balancers

The widows are Lawson impact dubble glass very heavy the balancers only have this Mark 23 DS 37.( 24 inch channel DS unknown maybe double strength . 37 could be pounds appears these are custom built for Lawson. Sadly because of the plastic pulleys they crush out after only 40 to 50 cycles eye have 14 Windows ever one of them let go and snapped. Learned the HARD way what not to buy .had those been all metal instead of plastic might have a chance.