Standard walking belt used on models: 831.293160 - E3800, 831.293161 - E 3800, 831.293162 - E 3800, 831.294140 - NORDIC TRACK E 3500, 831.294142 - E 3500, NTL15922 - 3100 RS, NTL17940 - E 3500, NTL17941 - E 3500, NTL17942 - E 3500, NTL18940 - 5600R, NTL18941 - 5600R, NTL19920 - E 3800, NTL19921 - E 3800, NTL19922 - E 3800, NTTL18514 - 5100R. NOTE: We strongly recommend you apply lubricant when you replace any new treadbelt.