Outdoor visibility marketing with indoor electronic message center tri color signs for window applications. Tri Color electronic message center indoor sign using the latest SMD technology with a matrix of 40 x 128. Change your message to your public every 30 seconds. This indoor electronic message center sign will fit inside any window up to 21 5/8 in x 63 1/4 in. It comes ready for installation. Built in wireless network using Guru Global C4 controller with cloud technology. Comes with a 3 year limited warranty.