Specify:-

• Wire Diameter
• Spring Length
• Number of Coils
• Length of legs and angle to one another, when free and under load.
• Direction of coiling
• Inside diameter. Allow for a decrease in diameter as the spring is wound up to avoid it binding on the rod or spindle around which it operates.
• Load at installed position and at operating position. Alternatively specify amount of deflection at any load.
• Rate of load per unit of deflection.