This free Max for Live Pack by Max for Cats contains three devices. A phase scope, an oscilloscope and a signal generator. All helpful tools for mixing in Ableton Live. More information.
The self-installing Live Pack only works for Live 11 and up plus Max for Live. The zip-file contains the same Max for Live devices, but makes them possible to be used for Live 10 (and possibly below - didn't test earlier than 10).
This is a free download. Simply add a "0" into the price field, unless you would like to donate something, which is always appreciated.