This is a 147 type connection kit for vintage Hammond console organs built from 1950 to 1975. It is “plug and play” - meaning no soldering or hooking up wires. It provides a 6-pin Leslie 147 type output (also works for 45, 145, 47, 247, 44w, 46w, 25, 125, and 225 type Leslies). This type of connection is also referred to as a "6W" output.
The kit plugs into the organ’s stock 5-pin Tone Cabinet output. 
Speed control switch plugs into the kit via 1/4” jack. The switching voltage is 5vdc, so is completely safe!
Can be ordered without a switch (provide your own), with a footswitch, or halfmoon switch.
As a bonus, a line level 1/4” output is also installed in the kit, allowing you to plug the organ into any amplifier/bass amp/PA system etc. This can be used simultaneously with the 147 output.