Made of 304 polished stainless steel, the PS-1 model is designed for heavy duty jobs in 5-10 gal. (20-40 qt.) containers. It easily fits any 1/2" electric chucked power tool. The PS-1 model is designed for a max speed of 800 RPMS. Tools with 450-750 RPMS get the best rate of thorough mixing. MIxers can be permanently installed if desired. Warning: This product can expose you to chemicals which is [are] known to the State of California to cause cancer and birth defects or other reproductive harm.