Yeah, that certainly doesn't seem to be a BX-type cable clamp. The ones I've seen in a certain DIY warehouse are roundish barrels with a set-screw to clamp on the metal jacket and a lock nut for the box.
The opening at the end where the wires exit is designed to hold the red bushing in place.
And yes. They're packed in clearly marked bags that have BX Connector or some such thing printed on them.
#114969 - 07/27/0308:43 PMRe: Why is the cable taped?
There's a kind of "BX" cable that has an aluminium sheath. Instructions and notes that come with it insist that you not use the "setscrew" clamps. But a style clamp that squeezes the sheath, similar to the clamp in the picture.
Anyone ever have the aluminium sheath to clamp connection fail when a serious fault current happened? I'd think you could get a bad connection due to corrosion of the aluminium.