Damaged packaging. Ph Wall Insulated Sleeve KIT22-28mm PIPE City plumbing 919157 RRP £53 The Diversitech Heat Pump Through Wall Insulation Kit TW KIT is a product designed to improve the efficiency of heat pumps by reducing heat loss through walls. Manufactured by Diversitech, this kit provides insulation that helps to maintain a consistent temperature inside the home while reducing energy consumption. It is a practical solution for enhancing the performance of heat pumps in well-insulated homes.