It's monr32 trunk lip mount, i have a few, the add is wrong, the range is 25 mhz to 1.3 gig , it'll leave the Austin spectra in the dust (so to speek) if mate it with a magnet mount then it's called a mon33, image thanks to Prcguy
Actually the MONR33 is a rooftop/deck mount antenna that requires cutting a 3/8" mounting hole. The MONR51 (newer model number) and the MON-51 (older model number labeled as only covering up to 470 MHz) were the magnetic mount versions of the Antenna Specialists scanner antenna.