This rebuild kit is for the 055/055B/3020/3021/3221 tripods with the round center column, and the center column locking knob that is removeable. There are two Versions of this kit: Double Spiral and Single Spiral. The spriral refers to the cam on the inside of the leg locks. The single Spiral will Only work with single Spiral leg clamps because the cams need to matchup to work. Conversely, the double Spirals will Only work with the double Spiral clamps. The Only way to know what you have is to remove the flip lever and look at the shape of the clamp, as shown on the right.
This kit contains everything you need to rebuild your old 055 or 3021 tripod: 3- replacement flip levers, 5- nut caps, replacement center column cover, replacement removeable center column lock knob and strap lug.
This normally retails for a lot more, but in this kit you get a special 10% off the regular prices.