MPQ3518 Features: * Transformers * Thermally protected * Fits standard wiring knockout * Class 2 energy limiting type * Quick clamp mounting allows quick and easy installation * UL / CSA listed * Case quantity: 20 Construction: * Thermally protected quality transformers, engineered to ensure long life with bells, buzzers, chimes, door openers, etc Specifications: * 120 VAC input * Volts: 16V10VA