Be careful.
If you are talking about dual switches (one in each stick, or one on the panel and one on a stick), do not use switches that have a non-momentary position, which is usually used for the flaps "up" position. If your flap switches stay in the "up" position after release and you leave it there on one of the flap switches, then it will override any subsequent flaps "down" command on the other flap switch.
The flap switch supplied with the Show Planes Flap Position System (SP FPS) has a momentary "down" position (meaning it will return to the middle, or "off", position after release), and an non-momentary "up" position (which will remain in that position after release).
In normal operation with the SP FPS, with a single flap switch, to set the flaps in a down position you momentarily depress the flap switch to the "down" position, and the flaps will continue to deflect to the first setting even after you release the switch, then if you momentarily depress the "down" position again, the flaps will deflect to the next down setting, etc. To retract the flaps, you simply place the flap switch to the "up" position and leave it there and the flaps will fully retract and stop automatically when fully retracted, but the switch will remain in the "up" position unless you move it to the "off" position.
If you want to use dual flap switches with the SP FPS, you need to install toggle switches with only momentary "on" positions (sometimes shown as (on)-off-(on) vs. on-off-(on) -- "(on)" meaning momentary). If you do this, then you will need to hold the switch in the "up" position until the flaps are fully retracted. If you release the switch from the "up" position before they are full retracted, the flaps position will remain where they are when you release the switch. The momentary down commands will operate normally.
For this reason (and the potential for unintended flaps actuation) I installed my SP FPS with a single switch near the throttle, and no flap switches on the Infinity grips.
I hope this is clear.
BTW: the flap switch(es) has to be able to handle 1 amp, which the Infinity Grip switches (and most panel swithes) will handle with no problem.