... and easy installation.Good looking and well practical stand.The frequency of alarm: 60 - 80 ... the following part:1, 0550R24L: 50 mm, red light modular, 24 VDC , Continuous lightening;2, 0550Y24L: ... VDC , Continuous lightening;3, 0550G24L: 50 mm, green light modular, 24 VDC , Continuous lightening;4, 0550Z24FB : ... 50 mm, S type 250 mm stand , black. EMA 50/70mm Multi-Layer Light Tower (led light tower)