Sometimes I travel a few hours to repair or service a relatives or friends watch and I take all the gear I need. Instead of taking my normal ultrasonic I pack this little 12v 45khz unit, and it is fantastic it's only 185x59x98mm in size. That's a 20mm wide watch band inside. Holds 500ml of water. Oh yeah I have 8 grown kids and 14 grandchildren. So there's always 2 birthdays and someone's watch to fix