BTR 120-500A Master-Fit® features:

Fits a variety of water connections. Three sets of water inlet and outlet connections located top, front and rear offer more flexibility, easy incorporation into any plumbing design.
Fits into tight spaces. New Master-Fit commercial water heaters are as much as one foot shorter than the commercial lines they are replacing. Plus, they feature low clearances to combustibles on all sides, top and rear.
Fits virtually any application. Master-Fit commercial water heaters can be installed independently, manifolded or connected to storage tanks. Choose from 14 new Master-Fit models with inputs ranging from 120,000 to 5000,000 BTUs and up to 100 gallons.
Fits your need for high efficiency. Master-Fit commercial water heaters operate at a high 80%+ efficiency - with a snap action diverter and automatic flue damper that minimizes standby losses, a Thermostat Dual Controller to limit water temperature stacking, and an intermittent ignition that eliminates a standing pilot.