The Worcester Greenstar Combination Boiler Greenstar 28i Circuit Board Holder Hinges is a compact storage tank water heater with an A+++ energy efficiency rating. Designed for use with a boiler heating system, this unit operates on 220/240V of voltage and is a reliable choice for central heating needs in the home. With the trusted Worcester brand and high-quality construction, this product is a valuable addition to any heating system. The circuit board holder hinges ensure easy access and maintenance for optimal performance.