The Mag-Funnel is a trough shaped funnel which terminates in the shape of a mag roller. In other words, it's the same diameter and length as a mag roller. There is a clip on the HP5000 and WX/8100 Mag-Funnels to hold the funnel on the hopper while you are filling. You hold the HP4000 Mag-Funnel in place with your hand.

Take the toner hopper and place it in a hopper fixture. Put the Mag-Funnel in the slot where the mag roller fits into the hopper. Pour your bottle of toner into the funnel. Toner will immediately flow into the hopper. You may need to help it a little by tilting or moving the hopper. The entire filling process should only take a couple seconds.