router table think invertedIf the top of the slot is important (as in no tearout) I suggest a downcut spiral bit.
If it's not important (tearout/fuzz OK) then any spiral bit or slot cutter bit will do.
After posting I remembered that MLCS has got some very good tutorials.
www.mlcswoodworking.com
Then the bit is also inverted. Upcut will cut toward the router or downward in a table. Still makes fuzzy edgerouter table think inverted