These earphone elements are the moving coil type, which are components of various headband and helmet-type headsets (and, where applicable, telephone handsets), which are a part of the Intercommunication Set AN/AIC-1 OQ. They provide communication for both ground-level and altitude applications as specified (see 3.1).

MIL-PRF-25670/5 (PIN M25670/5-01) has no material numbers [NSN's] assigned. However it is used on:

a. The Next Higher Assembly H-251A/U Headset, MN 5965-01-182-3384 and

b. The Next Higher Assembly H-161F/GR Headset, MN 5965-01-148-3396

All of the earphone elements specified under MIL-PRF-25670 should meet United States Air Force safety and hearing-protective standards for such equipment, and have been approved by:

"Air Force Research Laboratory -

711th Human Performance Wing -

Battlespace Acoustics Branch -

AFRL/711HPW/RHCB, Wright-Patterson AFB, OH

(Phone: 937-255-2203)

{Formerly identified as: Air Force Materiel Command, Human Systems Center, Armstrong Laboratory, Bioacoustics and Bio communications branch (AL/CFBA)}.