Can be used as either a right ascension or declination motor. The motor is controlled and powered by an optional Vixen SD-1 single axis or DD-1 dual axis drive controller. One MT-1 motor is needed for the single axis right ascension operation or two motors are required for dual-axis operation. When controlled by an SD-1 or DD-1, the accuracy of the MT-1 is within +/-0.005% of the sidereal rate. The optional 3828 Manual Clutch, described below, is needed if manual operation of either axis is to be retained. Compatible with Great Polaris, Great Polaris 2, Great Polaris D2, Great Polaris Economy, Super Polaris and Super Polaris DX Mounts. Optional SD-1 (3739) or DD-1 (3740) controller required for proper use.