Hi- thanks for posting!
Your balance system was very popular for wood windows in the 1940's to 1960's. For your wood sashes, you will need our Series 500-20 red tip balances with our 17-012 balance brackets. These brackets hook on the balance spiral.
To install these balances, you would drop them from the top on the side of the sash. Use our 33-017 screw to attach the balance tubes at the top. Now raise the sash and have someone hold it up while you attach the bottom bracket, our 17-012 with the 33-090 screw while the U-shape opening corrals the spiral. With your finger bring up the spiral to the bracket and attach the 75-005 tool and turn the spiral clockwise three turns.
Hook it to the fork of the bracket. Repeat the other side and try the sash. If sash creeps down, raise and hold up the sash and give the balances another turn or two.