Extension Spring Ultra Precision 302 Stainless Steel Plain End Type Full Twist Loops Overall Length 3/4 In Outside Dia 0.180 In Wire Dia 0.029 In Load 5.06 Lbs Deflection @ Load 0.28 In Initial Tension 0.45 Lbs Spring Rate 16.42 Lbs/In Meets/Exceeds ASTM A313 and AMS 5688 Package 3