Included in the Glidecam X-10 package are plates used to add weight when your camera is too light.  A  Glidecam camera stabilizer rig that is heavier will fly much smoother so adding larger disks on the bottom of the sled needs the extra weight on the top. These plates are added to the top of the rig to compensate for the weight added on the bottom. These plates are not necessary in all situations various bolts are to be used as camera screws when you’ve added the plates. The plates will create height so longer screws will be needed. Balancing instructions and setup comes with your camera stabilization system. One one of the best articles I have found on this subject is by Hank Castello that is short and easy to read..