Grandtau via Amazon offers its Grandtau Portable Air Compressor, model no. Tire-0002, for $26.98. Coupon code "6RD96MDM" drops it to $19.16. Plus, Prime members bag free shipping. (Non-members can spend $35 or more to qualify for free shipping; otherwise, shipping costs $6.48.) That's $58 off list and the lowest total price we could find. It features a 12-volt DC motor.