ms303LEV-MS303-DS. Mfr. Model # MS303-DS. Skip to the end of the images gallery . Skip to the beginning of the images gallery . Product Description. 30 Amp, 600V, Three-Pole, ThreeLeviton® MS303-DS Industrial Grade Manual Non-Grounding AC Motor Starter Switch, 600 VAC, 30 A, 20 hp Power Rating, TPST Contact SKU: LEVMS303-DS. Manufacturer Part Number: