ISO D Die Spring, Heavy Duty, Color Red, Chrome Silicone Alloy Steel, Finish Powder Coat, Overall Length 1-1/4 In., Outside Dia. 5/8 In., End Type Closed and Ground, For Hole Size 5/8 In., For Rod Size 11/32 In., Spring Rate 348.3 lb./in., Meets/Exceeds ISO10243