Just found the receipt. 3 piece set from AutoZone includes 12, 14, and 17mm bits for $7.99. 1/2 inch drive. I used the 14mm on my diff last night and it worked great.

__________________
Rick Miley
2014 Tesla Model S
2018 Tesla Model 3
2017 Nissan LEAF
Former MB: 99 E300, 86 190E 2.3, 87 300E, 80 240D, 82 204D Euro
Chain Elongation References