A 40T barrel ONLY by Diamond Pacific Tool Corp. is an industrial grade polyethylene barrel, SKU 611-14002. This barrel does not require any liner. Lids are made water tight for inserting a neoprene rubber gasket between the barrel and the lid. Weight of the barrel 5.5 lbs. and will hold 40 lbs. of stones and media.. The photo shown is for the complete tumbler to give you an idea of what the barrel looks like.