The groove defines a groove wall (20).

At the same time the block tumbler (BZ) with the counter tumbler (BG) in position (P1) also serve as coding tumblers.

The tube groove (64) is aligned with the flange groove (46).

A circumferential carrier groove is defined in the ring carrier, the carrier groove being concentric with the piston groove.

A flap (3) is designed to block the groove thereby locking the band (2) in the groove.

The throat end (28) is intubated into the throat (T) of the person (P) with the flaring helping create a seal within the throat (T).

The cylindrical wall extends from the top surface and includes a first ring groove, a second ring groove, and a first land between the first ring groove and the second ring groove.

The tube connector mates the flange groove (46) and the tube groove (64).

The carrier ring has an outer annular groove and an inner annular groove.

The distance between a part (20) of the relatively wide throat (19) from the relatively narrow throat (18) is greater than the distance between an opposing part (21) of the relatively wide throat (19) and the relatively narrow throat (18).

The groove (34) continuously extends in the circumferential direction, and the radius of the groove is constant.

The tumbler may be stimulated by an impulse of mechanical energy, and, after stimulating the tumbler, the vibrational response of the tumbler may be detected over a period of time.

The finger can extend toward the throat and is adapted to retain the flexible member within the throat.

A first groove has a first groove portion defined by a second radius extending from an arc center (408) of the first groove portion.

The radius (C') of the gullet (13') is larger than 1/2 of the depth (D') of the gullet (13').