This is a RCBS known as the Sidewinder, model 87067.
Walnut shell media is the fastest way to clean and shine your brass in a dry tumbler. RCBS' Formula 1 walnut shell media is ground to 12/12 sieve size" and treated with case polishing additives - perfect for cleaning your brass quickly to "like-new" condition!
Treated with case polishing additives
Walnut shell media