Serial numbers for Jacuzzi® Jetted Bathtubs are located above the pump on the bottom of the bathtub. This is visible through the required 12”x 18” equipment access panel for drop-in bathtubs. To access the serial number on a skirted Jacuzzi® Jetted Bathtub, remove the access panel to gain access to the equipment. The serial numbers include a combination of six alpha and numeric characters.