This lid is a modern, better than original replacement lid for the R-3 #905 lid. This lid is made from High Density Acrylic. Factory original lids are made from HDPE plastic, while good for strength, it has a very poor resistance to abrasion. As you may well know, these lids may wear thin after only a few tumblings causing leaks. The acrylic replacement lid here is far Superior to factory original, in both strength and abrasion resistance. The physical property comparison of the two materials is bellow: ACRYLIC HDPE Density 1.18g/cc .96g/cc Hardness, (Rockwell R) 110 50 Tensile Strength 8000psi 3200psi These lids are over Twice as strong as original lids. This lid will replaces both old and new style lids, and will fit perfectly. This is a non factory original R3 barrel lid, #905 for the popular Thumler's Tumbler brand Tumbler/Polisher. This lid fits the 3lb Barrels of the Model T, and A-R1. It also fits the 6 lb A-R2 barrels. The lid and ring included are not Factory Thumler, but work just as well. This sale is for the lid and ring only, no tumbler included, just one replacement barrel lid and one retainer ring. **This Lid Is Better Than** **Original Factory** This lid is approximately 4 inches in diameter, it will only fit the R3, 3lb. tumbler series. Sale Is For One(1) Brand New Lid and ONE(1) Retainer Ring Only, NO Tumbler, No Other Parts, Just What is In The Pictures.