The #10 clamp-on hand grinder has a 3 3/8″ x 4″ hopper opening. This grinder comes with 3/8″ and 3/16″ plates and a knife. Cast aluminum and well made for long lasting service. LEM replacement knives will fit but will be a bit loose. LEM replacement plates will not work with this product. For the best fit, please order the plates specific to this grinder.