The Stiebel Eltron Tempra 24 Plus on-demand water heater has a water-temperature dial and LED ridge. As part of the installation, the author included an Aqua-Pure AP430SS Scale Inhibition System, which has a consumable water-treatment (white) canister.
A 7-port closed-end Sioux copper manifold is concealed behind an access door. Printed sheets attached to the back of the door indicate which manifold port is connected to the various plumbing fixtures in the house.
The red knob is part of the Watts mixing valve and can be rotated to adjust the mix of hot and cold water to achieve 120°F. Above the mixing valve is the hot-water supply line to the manifold, complete with a dial thermometer to measure the mixed water temperature and a ball valve to isolate the hot-water manifold.