In a message dated 12/21/2003 7:23:47 PM Eastern Standard Time, Neuroray writes: Could you please let me know where you can purchase engine-block heaters like the ones you have? Thanks, EFV. Mine were already installed when I purchased my boat..one of the few things that worked. So I have no confirmed source. BE VERY CAREFUL here. Get professional advice about the location of the block heaters in your engines ...preferably from the manufacturer.....water must circulate within the engine enough to avoid boiling and air bubbles at the block heater..if not they will repeatedly burn out....A neighbor had mechanics installing them in 671T's and they gave up because of repeated failures..... I can tell you mine are 1200 watts each and are thermostatically controlled by room thermostats...in other words, the unit stays on until the engine room air surrounding the engines is warmed...this system works fine in my boat but other arrangements may also be available....At 45 to 50 degrees ambient, the heaters warm the engines enough in 45 minutes to an hour for a clean easy start with little smoke.... One source you can try is Mid Atlantic Engine Suppy, online, as they have helped me with other engine issues....also there is a diesel engine website, boatdiesel.com, that may be able to help.... good luck... Cheers, Rob Brueckner 1972 Hatteras Yachtfish