Horiso® Rack Arm Systems (or skylight louvres) comprise of a series of support arms (rack arms) onto which slats are mounted. The rack arm design incorporates a tilt shaft to enable rotation 0˚- 95˚, from fully open to fully closed. Horiso Rack Arm System®, are designed specifically for solar shading on sloped and shaped glazed areas. It is a non-retractable system with a range of slat sizes. The 80R, the roll formed rack arm system and 4 extruded systems 75E, 88E, 145E and 155E are suitable for both interior and exterior use. Systems 88E and 155E also provide total light exclusion with the addition of brushes installed at both sides of the system. Horiso Rack Arm Systems can be operated manually with a crank handle or motorized, utilizing Horiso EZ1 ZigBee PRO WiFi or Horiso EB2 hardwired motor controllers.