For a limited time Walmart is selling the Stanley 'FatMax' 700-Amp Peak Jump Starter with Compressor & Road-Side Service for only $39.88. This current pack lists for $100, and Amazon is selling the same jump starter for $20 more.

The compressor/jump starter combo pack has gotten a high 4.2/5 stars from over 2,100 reviewers at Amaozn, features a 120 psi compressor and guage, USB port and 12v power outlet.