Frigoboat Capri 50F compressor/condenser with a standard controller and manual compressor speed selection board. Because Danfoss/Secop BD50 compressors are multiple speed, Frigoboat allows you to choose the most efficient rpm to run your compressor at to get the job done. Run it fast to bring the box temperature down quickly; run it slower to maintain your box's set point. Save on energy! The Capri 50F is best used with refrigerator boxes 7-18 cu ft or freezer boxes 4-9 cu ft. Recommended option is to replace the manual speed selection board with a Merlin automagic mini smart speed control board (E52152). It has an algorithm that will automatically adjust the comrpessor's rpm for you, plus there is a compressor fault indicator light that will blink, should your compressor stop for a fault reason, 1-5 times to tell you where to look for the problem.