A "reg" is someone who plays at least somewhat regularly and wins. A "rec" is a recreational player. This recreational player can play frequently or infrequently.
Here Are a Few Ways to Exploit This Specific Poker Player Type
1
Steal his blinds a fair bit (Fold to Steal is 82%)
2
5Bet shove with a bit wider range than normal (4Bet of 3% is a little bit higher than most Full Ring regs at these limits)
3
Triple Barrel (Fold to River Cbet of 100%)