If you do not have a vertical surface to attach the V-Lock base, this is the answer.
These shims or wedges are in the shape of the V-Lock base and are designed to adjust the alignment so that the base is vertical.
They are made of Starboard* and come in 3 sizes.
The smallest is 4 degrees, medium is 7.5 degrees and large is 11.5 degrees.
They can be combined to make up larger angles, so if you needed to make up about 20 degrees you would use a combination of a medium (7.5) and large (11.5) to make 19 degrees. Well I guess you would still be off by 1 degree, but you are close!
There are no holes drilled through the wedges as our experience and that of some customers advise drilling through the V-Lock Base, the wedge and boat all at once.
*Starboard is UV Inhibited high density poylethylene (HDPE)