Model # 53200 CTC 511,521,5 PROGRAM T-STATE3 Series universal thermostats are easy to install, easy to program, and easy to operate, taking the stress out of getting confortable.Features/Benefits:Easy InstallationColor coded wire terminalsBuilt-in level bulbBreak-away guides for less common terminalsScrewless terminalsBlue backlikghtPermanent memoryFilter monitorSystem powered, or battery powered (2AA, included)Battery backupFreeze protection3 year warrantyTerminations: Rh, RC/R, Y, G, W, L, O, B, AE/W2, Y2, C, A25% fewer programming steps4 programs per daySave-Away override