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Our 4-betting range generally consists only of the very best hands: JJ, QQ, KK, AA and AK, say. This is even tighter than GTO, which will throw in some weaker bluff combinations to balance the 4-bets that are for value. HJ position calls 1 BB (20c).

A good winning 6-max reg will typically have a 4bet range in the region of 4-5%, whereas the average player has a 4bet range in the 2-3% region. In other words, it's not a big deal to slightly overfold when facing a preflop 4bet from an unknown.