The 32-20-XH is ideal for situations where a large load needs to be supported but adding additional height is a concern.  Each dual wheel caster is capable of supporting 400 lbs but only has an overall height of 3.25 inches.  The hard rubber wheels come with a ball bearing to make moving the weight easy.  This is a great economical option for supporting up to 1,600 lbs per set of four casters while adding minimal overall height.