This is our representation of a Rickenbacker-style bass bridge such as that on the venerable 4005.  It differs from the bridges of the late 50s and early 60s in that it is designed from the jump as a bass bridge rather than being a converted guitar bridge.
 
Center-to-center distance from the E saddle screw to the G saddle screw is 2".  The default saddle radius is 10"; please let us know if you need something else.