If you've ever seen upgraded wood you'll know what the difference is! Plain wood, usually Walnut, has straight grain and even color not unlike the Mossburg shotguns at Kmart. Upgraded wood is cut from the crotch of the tree and has swirling grain with various color variations. A truly fine piece of Turkish Walnut can be spectacular. Does it make the gun shoot better, of course not, but it sure is pretty to look at.