Just going to try and simplify this and post what it says from the Home Depot promo page.
"Tis the season for savings! Get a tool free when you purchase the RYOBI 18V ONE+ 3.0Ah Battery & Compact Fast Charger Starter Kit. Choose from over 50 eligible tools, up to a $129 value, including select tools from our brushless lineup, woodworking tools, vacuums, lights & audio, even new releases, and so much more. With so many great options, which tool will you choose?"
Kit contains 18-Volt ONE+ LITHIUM+ HP 3.0 Ah Battery (2-Pack) Starter Kit w/ Charger and Bag
This also includes one bonus tool of customer choice . Don't forget to get your 10% discount if you are military.
Currently I only see 29 of the 50 optional tools available on the Home Depot website.