hot tub spa heater element flo thru 4kw 240v 1kw 120v 10"replace balboa m7 heat proline 1 heater element per package one of the most common spa heating elements. comes complete with stainless steel mounting nuts, electrical nuts, washers and new o-rings. easy to install. this replacement elements fit most 2quot; diameter stainless steel tube style heater manifolds. used in many models of balboa, cal spas, coleman, brett aqualine, spa builders, catalina, gatsby, hurricane, asi, gecko, nuwave and many more. this is not one of the cheaply made black steel or coated elements. this is a top quality stainless steel alloy that offers high strength and resistance to oxidation. 4kw at 240v 1kw at 120v 10quot; overall 1.25quot; between terminals, center-to-center