MRCOOL DIY 4th Generation E Star 24k BTU Ductless Mini-Split Heat Pump Complete System 208-230V/60Hz The MrCool 4th Generation DIY 24K BTU, 20.5 SEER Ductless Heat Pump is an all in one system that seamlessly combines efficiency, durability, and simplicity.This system can offer a 20.5 SEER efficiency rating that has allowed it to achieve an Energy Star certification and can heat & cool an area up to 1,000 sq. ft. It also features durable construction and a corrosion-resistant Gold Fin condenser.All of this is contained within a Do-It-Yours