Made of 304 polished stainless steel, the ES model is designed for medium to heavy jobs in 2-5 gal. (8-20 qt.) containers. It easily fits any 3/8″ electric chucked power tool. The ES model is designed for a max speed of 1000 RPMS. Tools with 450-750 RPMS get the best rate of thorough mixing. Mixers can be permanently installed if desired.