What do you think, a stop+go bluff?

PokerStars Game #10969734121: Tournament #55429369, $20+$2 Hold'em No Limit - Level V (75/150) - 2007/07/16 - 13:12:00 (ET)
Table '55429369 3' 9-max Seat #7 is the button
Hand History Converter from Poker-Theory.org

Seat 1: Acesup803 (2985 in chips)
Seat 2: SABK (4115 in chips)
Seat 3: granleif (6718 in chips)
Seat 4: Toni-Mark (3682 in chips)
Seat 5: LeftyB (3672 in chips)
Seat 6: TruGrindr (8090 in chips)
Seat 7: Hero (9505 in chips)
Seat 8: BerkekeyNick (4390 in chips)
Seat 9: PandeAA (2460 in chips)
BerkekeyNick: posts small blind 75
PandeAA: posts big blind 150

*** PREFLOP ***
Dealt to Hero

Acesup803: folds
SABK: folds
granleif: folds
Toni-Mark: folds
LeftyB: folds
TruGrindr: folds
Hero: raises 300 to 450
BerkekeyNick: folds
PandeAA: calls 300

*** FLOP ***

PandeAA: bets 600
Hero: folds
PandeAA collected 975 from pot
PandeAA: doesn't show hand
*** SUMMARY ***
Total pot 975 | Rake 0