While your best reception results will come from antennas that don't use through-glass technology (but rather continuous wiring such as a mag-mount), this full coverage antenna (25 - 1300 MHz) will perform adequately for most mobile scanner installations. It's also a great choice in that it looks like a cell phone antenna and of course won't scratch your car's body such as a mag-mount might. It's easy to install with no holes to drill. It has a 29" colinear whip, 17' of RG58 cable with a BNC connector.
Product Specs:
Coverage 30-1200MHz29 inches tall17 feet of RG58 coaxBNC Connector