They Simply fit into the existing holes on your hot tub . The distance between the lugs is 10.5cm (centre to centre).
LX WTC120-AB Pump - 1.2HP, 1Speed, 1.5"x1.5" for Blue Whale Spas/Storm Force 7
LX WTC200-AB Hot Tub Pump - Blue Whale/Storm Force 9, 220-240V/50Hz
Happy HHTRB50H Hot Tub Filter Fits Pleatco PRB50-IN C-4950 Tubs Blue Whale RD50
Balboa 6 Button Hot Tub Tp600 Topside Controller (With Blue Whale Decal) #2 Used
Darlly PWW50 SC714 Filters 6CH-940 Hot Tub Superior Spas Spaform Blue Whale Tuff
Happy Hot Tubs Replacement Black Pillow for Blue Whale Spa Headrests Spas Tub
