Extension Spring Ultra Precision 302 Stainless Steel Plain End Type Full Twist Loops Overall Length 5 In Outside Dia 0.500 In Wire Dia 0.055 In Load 11.38 Lbs Deflection @ Load 6.10 In Initial Tension 1.04 Lbs Spring Rate 1.74 Lbs/In Meets/Exceeds ASTM A313 and AMS 5688 Package 3