The Mars System is a pre-rigged/pre-packaged 4:1 mechanical advantage lifting-lowering system using a double camming pulley. It is designed to lift and lower live loads and as such may be used for rescue or entry into confined spaces. All components used in the Mars System exceed the current NFPA, ANSI and OSHA requirements. No more fumbling about looking for parts to build a mechanical advantage system and no more scratching your head trying to remember how to assemble the parts! Thanks to the 4:1 mechanical advantage, it is easy to lift a 2 person load and then some. Unlike other manufacturers, we rig the Mars System with 1/2" NFPA 2 person rated rope. The maximum safe working load at the load end of the system is 1,760 lbs.and 440 lbs. at the cam.