Each Tibbit device has a label which states this Tibbit's number and function.
A small 2D barcode (micro QR type) encodes the Tibbit number as well. This number is a 4-digit code. First three digits in the code represent Tibbit number, and the fourth digit indicates the device version (some Tibbits have more than one version available).
For example, if the code is 0032 then this is Tibbit #03, version 2: