It's a 5Ws
Special long excursion
subwoofer.
136mm (5-3/8") subwoofer for small bass reflex enclosure.
40mm (1-3/8") v.coil,
100mm (4") magnet
Impedance: 5Ω
Max. power handling: 160W
Nominal, power handling: 80W
Sensitivity (2.8 V/1m): 87dB
Frequency response:
45Hz*-2.5kHz
That's right it's a 5-3/8 Sub. Aint no mid bioch!