The switches do not have a number on them except o27. I purchased two RH switches online. One came in the a blue box and the other in a red box? Blue box K-O276(?) and red box K-O376 (?) Both have the bulb lights not the LEDs. I am trying to run them with fixed track voltage with my Lionchief loco. One buzzes when I throw it to "out" and the other non-de rail fails. I like them because with no power connected they keep the Lionchief on tracks better than Lionel switches like the #5168. I followed the wiring diagram that came with them and wired the same way as another K-Line 276 on the same loop that works fine. Thank you for your interest and maybe help?