I don't think they are quite as light as stamped steel, but pretty close. I don't have anything accurate enough to weigh them on to check. They are die cast and much lighter and thinner than the sand cast FE valve covers like the original '67 Shelby GT 500 Cobra LeMans covers. Personally I like the 428 "Snake" die cast covers better myself, but that's just my opinion and both look good. Both styles are being reproduced and are much less than $400, and I think that's keeping the price of originals down. I've never paid anywhere close to $400 myself, but I guess I don't know the going rate. A lot of parts people knew were special years ago were usually saved before a car got scrapped - Aluminum intake manifolds, Holley carbs and the fancy valve covers to name a few, and many survive today.