They both switch to earth, but the front switch (with the "2") latches, the rear one doesn't.
The rear fog lamps switch makes a momentary path to earth for an ECU that does the actual rear fog lamp switching.
The front fog lamps switch switches a relay's coil to earth.
If you're not too worried about the symbol on the switch's face, you can use a Puma Defender heated seat switch (
YUF500150LNF), which costs a fiver.
This switch is a latching live-switching switch.
You could use a Puma heated seat switch and swap the front for a rear fog lamps switch, that combination would only cost around £12
The Puma switch uses the Black 5-way switch connector (see my signature or PM me
)
More info, here -
http://www.landyzone.co.uk/lz/1534634-post8.html
.