Shafts, propellers, couplings and screws are stainless steel. Mounting frames are covered with resilient rubber to virtually eliminate vibration. Propeller blades should be kept 2" from bottom of the container for proper mixing. Shafts can be sized and cut off for your specific container application. Spare shafts and blades are available for both mixers and should be ordered with mixer to assure proper fit. Not for mixing flammables. Special Mixer - Mixes 1 - 20 gallon capacity mixing jobs. Comes with 5/16‚Äù diameter, 18" long, type 316 stainless steel shaft and 1 - 2-1/2" 316 stainless propeller blade. Motor is 1/40 HP, 1550 rpm, 110 V., 60 Hz., open drip proof. Mounting frame is 4-1/2" W x 18" L.