ISO D Die Spring, Medium Duty, Color Blue, Chrome Silicone Alloy Steel, Finish Powder Coat, Overall Length 3-1/2 In., Outside Dia. 5/8 In., End Type Closed & Ground, For Hole Size 5/8 In., For Rod Size 11/32 In., Spring Rate 85.7 lb./in., Meets/Exceeds ISO10243