Amazon offers the Reese Towpower Towing 2" Starter Kit
, model no. 21536, for $19.98. Clip the $5 off coupon on the product page to drop the price to $14.98
. Plus, Prime members receive free shipping
. (Non-members can spend $49 or more to qualify for free shipping; otherwise, shipping adds $8.85.) That's the lowest total price we could find by $3, but most merchants charge $22 or more. It features a 9" shank and includes a ball mount.