ISO D Die Spring, Extra Heavy Duty, Color Yellow, Chrome Silicone Alloy Steel, Finish Powder Coat, Overall Length 7 In., Outside Dia. 1-1/4 In., End Type Closed & Ground, For Hole Size 1-1/4 In., For Rod Size 5/8 In., Spring Rate 524.2 lb./in., Meets/Exceeds ISO10243