Part of the efforts to keep LP turntables selling although CD already was on its way to grand success, the Flamingo was in the higher side of things with a Quartz-Locked direct-drive motor, built-in phono EQ and a linear tracking tonearm - far from the PRP5, AT727 or even the pretty PS-Q7.
The big one, PS-F9, sports a motorized clamping system (behind the Sony tag), a magnificent slightly off-white finish with pearl-like coating (now you see it, now you don't - but you never see it in Sony's own images), a pair of mini-jack headphones' outputs, a built-in cleaning brush next to the tonearm and, for the JP models, like the PS-Q7, an FM transmitter (but without a LED-lit antenna) ; the Line-Out mini-jack circumvents the volume ring.
The PS-F5 is the more common and simplified version : no quartz-locking, no FM transmitter, no line-out and only manual disc clamping. And no pearly-white finish coating either ; that coating had a long-term side effect : F5s yellow a lot, F9s don't.
Both are to be operated with batteries but optionally provide a jack for 6V DC power source ; they can be used horizontally, vertically or even hung on a wall.
A LED dot facing the headshell allows to see where the arm actually is (plus battery power display) ; the retractable feet are very much part of the charm of this quite perfect design.
The serial number sticker, inside the battery compartment, reveals a 5-digit system often used on Sony's in-house but "special" products.
The packaging (kraft-cardboard at first, then white, both with two-tone red [or blue] imprint) wasn't as clever and elaborate as that of the PS-Q7 but after all, unlike the latter, the Flamingo was portable on its own.
Sony sold manymanymanymany F5s and manymany F9s but they are both rather rare today. I have an F9, it works very well (stable speed, decent noise floor) and I'll never ever let it go.
A clean description of the F9 here ; a dedicated website here (with safety instructions regarding the 6V input), Sony's own completely bland page here and a small view of the early packaging here.