Pebble is a series of water heaters with different design details. They are square or rectangular and feature modern muted colours. The units are operated via a large rotary knob with an illuminated ring, a small rotary knob with a scale or a touch display. The design elements can be combined to adapt the unit’s visual appearance and ergonomics to its surroundings. Thanks to the characteristic design language, product line affiliation is recognisable at first glance.