Aftermarket Safety Bar replacement spring. Direct aftermarket replacement for part number: 6664207

Fits Models: 450, 453, 520, 542, 543, 630, 631, 632, 641, 642, 643, 730, 731, 732, 741, 743, 751, 753, 763, 773, 843, 853, 863, 873, 953, 7753