The Aqua-Shield from AquaMotion is a water-saving hot-water recirculation pump/system for outdoor installed tankless heaters without a built-in pump. Its built-in timer and sensor are fully automatic and work with one pipe and dedicated return line systems, On Call (OnDemand) and undersink Aqua-Flash bypass valves. It includes a tamper-proof protective, lockable housing against rain, sprinkler spray, humidity and freeze. It provides hot-water comfort when needed while saving 7,500 to 15,000 gallons of water annually. 401-785-3000; www.aquamotionhvac.com.