Continuous Hot Water for Multi-Tasking: Mizudo tankless water heater provides hot water within 10 seconds at 3.6 GPM and 80,000 BTU, suitable for homes with bathrooms using 2-3 low-flow fixtures Energy Efficient Operation: On-demand heating, tankless water heater only consumes gas during use. Oxygen-free copper heat exchanger provides faster heating than standard steel models Third-Party Certified Safety: All tankless water heaters propane are UL listed and CSA certified to meet US safety standards for gas appliances. Includes 2-year whole unit coverage and 5-year for heat exchanger Integrated Protection System: This propane tankless water heater is provided with built-in safeguards such as freeze protection, leak detection, overheat cutoff, and wind-resistant ignition US Home Compatibility: The lp gas tankless water heater indoor is compact 20.5 x 13.0 x 7.0 in. Natural gas powered indoor unit. Operates on 120V power with 3/4" NPT connectors. UEF >0.81