CR2032 Coin Battery you need: https://amzn.to/3GkOJnNHow to replace the battery in this key fob for the Acura MDX 2014, 2015, 2016, 2017, 2018, 2019, 2020 "Smart 4Button" key fob. See the whole guide at: https://fobbattery.com/howtoreplace...