This fits your. Make sure this fits by entering your model number. POLISHING BARREL allows you to polish like a pro. We recommend having a dedicated barrel that is only used for the final step in the polishing process to avoid leaving any remnants of rougher grits that might scratch your gemstones and diminish the final polish. COMPATIBLE with National Geographic Professional Rock Tumbler and Discover with Dr. Cool Professional Rock Tumbler 100% SATISFACTION GUARANTEE when you buy from Discover with Dr. Cool!