Land Rover Series 1 2 Smiths Clayton Conversion Heater Motor Mounting Spacers. 

Conversion set of 3 UK hand-machined spacers with associated nuts, washers and spacers all in stainless steel.

These mount the new Clayton Matrix into a Smiths heater with the old motor.

(See here for mounting with a new motor)

These mounts are approximately 61mm long and the heater mount spindle is 26mm long with 13mm threaded section.