The VTB EN54 Part 3 and 23 approved sounder and VAD beacon is part of the VTG/VTB family of products. It comes with 32 selectable tones plus a selectable override tone. The device features a changeover facility from Alert to Evacuation tone when installed using a three-core cable. The visual alarm device is available with white flash (C-3-8 coverage) or red flash (C-3-7 coverage) and is fully synchronized with the sounder function. The flash rate is 1 Hz by default, with 0.5 Hz selectable via a DIL switch. Shallow base versions are rated IP21C, deep base versions are rated IP33C and independently certified to IP65. The sounder and VAD functions can also operate as a beacon-only unit. Installation is via a twist and lock bayonet mounting system, with a removable cover on the deep base for surface wiring and a base locking system as standard. Body colours are available in red or white. The device is approved to EN54-3 for sounders and EN54-23 for visual alarm devices and is suitable for conventional fire alarm systems including two-wire SAV-WIRE setups.