Looks like that is just the base. Not the whip. Do you have another eBay link so I don't get the wrong thing. Also if the antenna is shorter is my reception worse? I live in a fringe area and need all the help I can get.

EDIT I found a 16 inch mast and a separate gasket. Ordered 2 of each and total was less than $6. Hopefully these work but the investment was low.