These Compact 400w units from Maxigrow have an encapsulated choke potted in resin in an injection-moulded enclosure which ensures silent running. The smart ignitor is also timed to protect against lamp failure. The ballast is wall mountable. Available with Euro & Diamond reflectors with Dual Spectrum Son-T Plus or Metal Halide lamps. Approximate maximum coverage 90 x 90cm. Conventional ballasts rely on simple and basic air vents in the outer case to cool and protect the internal components. The Compact range of encapsulated power packs take advantage of the entire enclosure to dissipate heat from these components resulting in greatly reduced internal temperatures compared to vented power packs. They are also very reliable.