Casing manufactured from heavy gauge galvanised sheet steel.50mm thickness of M0 glass fibre internal acoustic insulation.External rotor motor, speed controllable, Class F insulation.External wiring terminal box.Safety thermal overload protection.MotorsOuter rotor motors.Single-phase models 230V-50Hz, IP54 or IP44 depending on models, adjustable via voltage inverter.Three-phase models 230/400V-50Hz, IP54, Class F, controlable by frequency inverter.Additional informationThey can be installed in any position.