I purchased the XXXHeat 600W for my Regal 40′ cruiser. Installed the unit between my Volvo engines just as Xtreme heaters recommended. For such a small unit this heater really supplies a great amount of heat for my engine compartment. I am really impressed with the amount of heat the unit produces. My boat stays in the water year round without winterizing which gives me the opportunity to use my boat during the winter. Thanks for such a great product. Mark Potter, Louisville, TN Before & After Xtreme Heaters Saved me Large Winterization Bills!