Like the Shimano XT bolt much of the XTR seat bolts weight comes from the steel used for the rod, housing and cam system. It uses a traditional internal rotating cam to cinch and tighten the post in place. The housing for the cam is made of cast steel that is chrome plated.
The threaded rod is also cast of steel, has the threads cut, and is then cadmium plated. The base of the threaded rod has a hole through it, that the lever slides into after the it passes through the cam housing. The lever, cast of steel and then given a dull nickel finish, is held in place by a cir-clip within the housing, so that the separate parts can't come loose.
The lever has no plastic jacket like the XT bolt. All the remaining parts for the XTR bolt are made from aluminum. The nut appears to be machined from aluminum rod, with a recess around the circumference for an O-ring to provide a steady grip while threading the nut on initially. There are two aluminum spacers, one closes off the cam housing with a volute spring compressed inside that makes the bolt "pop" open when the lever reaches the release point. A smaller spacer butts against the nut. These three aluminum pieces are anodized a grey color that alludes to a Titanium color. The largest distance the XT seatpost bolt will close on is 28mm, the smallest distance it will close on is 17mm. The prototype we were provided with had a separate aluminum slip sleeve that covered the threads of the bolt. This sleeve serves no real purpose and probably won't be a part of the production model, our weight therefore will not include the weight of this sleeve. The XTR quick release bolt weighs 66 grams. Made in Japan. These haven't been seen as an after market item since 1993.
When they were still available we sold them for $15.99