The Jacuzzi/Sundance 6600-722 is a control circuit board for LX-10/LX-10L spa systems used across the 680 Series, Sweetwater/Del Sol, and J-200 platforms. It is a dual-voltage (115/120 and 220/240 VAC) PCB with three power relays for 1-pump, no-circulation-pump configurations; common chip revisions include Rev 5.03+ and Rev 5.57, some versions use surface-mount heater terminals, and it supersedes 6600-042, 6600-089, and 6600-289. Compatible units include Jacuzzi J-210 and J-220 (circa 2005-2006) and Sundance 680 Series Denali and Tacoma (2006+), as well as Del Sol/Sweetwater models such as Redondo and Hermosa (2003-2005).