My shackles are 10,450 wll with a 6:1 safety factor (so shoukd not break till 63,000 lbs), tow strap is 20k with a 40k breaking strength. I have the bigger ARB snatch block 9,000 with a 38,500 break strength... if you can tell I don't want heavy things shooting out at mach 5 if they were to break.