Quantrex Q140 Ultrasonic Cleaning System is ideal for clock, watch, jewellery, and fine tool cleaning. It is constructed of metal and stainless steel, using only the finest materials and workmanship. The Quantrex Q140 features a 30 minute/ hold timer, which allows you to set the cleaning duration or set continuous run. This machine has a built-in heater with a separate on/off switch. This allows the user to decide if the function is activated or not, depending on need. L & R stands behind the superiority of their product with their unprecedented 30-60-120 warranty.