Vexilar 9 Degree High Speed Transducer Product code :TB0030. $119.95
Came with my FL-12. Everything you want to know about cone/beam angle, including a chart showing the area of coverage for 8, 9, 12, 19, and 20 degree cones at given depths. http://vexilar.com/blog/2014/08/28/choo ... beam-angle