LR4 Series Tower Lights have a modular "Twist and Lock" system that easily customizes and reconfigures LED modules and sound modules. Pre-assembled 2, 3 and 4 tier LED modules are available, and a fifth tier can be added. LED modules are interchangeable and color sequences are changeable by adding or removing up to 5 color module choices even after installation, and with no tools needed. LED modules of the same color within a signal tower will light up simultaneously. Prism-cut lens design enhances LED visibility from any direction. LED module colors correspond to color coordinated wiring so re-wiring is not necessary. An optional alarm module is available with adjustable volume and selectable sound patterns. The maximum sound volume is 85dB at 1 meter. LR4 series tower lights start at $65.00 and are NEMA type 4X and 13 rated.