Made of 304 polished stainless steel,? the PS-2 model is designed for heavy duty jobs in 10-50 gal. (40-200 qt.) containers. It easily fits any 1/2″ electric chucked power tool. The PS-2 model is designed for a max speed of 450 RPMS. Tools with 450-750 RPMS get the best rate of thorough mixing. Mixers can be permanently installed if desired.