This is a steel compression spring, similar to the one used in the 2017 game FIRST STEAMWORKS?.
This spring is slightly stiffer than the McMaster-Carr 9664K68 spring. Notice below that the spring deflection for the AndyMark spring is 1/2" less than the McMaster spring when they both hold on 10 tooth gear.
Specifications:
- Length: 9.0"
- OD: 0.875"
- Wire Diameter: 0.135"
- Weight: 0.64 pound
- Material: Tempered Steel