This is a Metra brand Flexible Dipole Antenna. This is a super simple antenna with a standard motorola style end. 

48 inch (122cm) long cable

Easy to hide

These types of antennas work less good than a fender mounted antenna, but they have their place. 
I use these on boats and hotrods where you wont be drilling any holes for the antenna. And also in my shop to have an antenna and radio reception inside of a building/garage.