Electrolytic de-composition has always been a problem since the introduction of composite masts and spars. This slowly damages the aluminium or carbon unless barrier paste, adhesive or a thin layer of plastic is used to keep the dissimilar compounds apart, which is always messy and time consuming.

This has been eliminated by the introduction of our insulators.
The Clamcleat® PT420&21 fits our Mk2 Racing Junior alloy cleats and look especially good with the hard anodised versions. 
The countersink cones fit under the screw or bolt heads and the baseplate fis under the alloy cleat. This prevents galvanic corrosion of the alloy cleat by keeping it separate from the fixings and surface. Quick and easy to fit. The base will flex to fit any size of tube. 

The cones are flexible enough to fit the slightly different size and shape of heads on self-tapping screws and bolts. Do not overtighten as you will just distort the cone. As long as the cleat does not move, it will be fine.
The screw holes in the base are designed to be a tight fit for the screw/bolt, to make sure that these are insulated from the cleat.

Test results from our own aggressive salt water testing, have proven these insulators really do eliminate corrosion problems.

The PT420 cones are available separately, for use with other fittings that use No8 (M4) fixings.  Please contact us.

The PT420&21 insulators are designed for use with these alloy cleats-
CL211 Mk2 Racing Junior.
CL211 Mk2/S2 Racing Junior with Becket.

Two other sizes of insulators are:-
PT422&23 for all M1 Racing Junior alloy cleats.
PT424&25 for all Racing Micros size alloy cleats.