LEISR399_INT will refer to the calibrations for the revised antenna mount design
LEISR399_INTA will refer to the calibrations for the original antenna mount design
Users will be responsible for knowing which antenna version that they are using. Leica also advises that any older SR-399’s with the original mount design, that were submitted for servicing were automatically upgraded to the newer design. Users should check their service records or contact the manufacturer if they are uncertain which antenna version that they may have.