The MK-1564( )/AIC contains a linear earcup transducer assembly with improved far field noise attenuation properties over the MK-805A/AIC, it also contains the microphone, Linear M-162/AIC which is a noise-cancelling dc powered with gain microphone. The MK-1564( )/AIC is intended for use in the improved SPH-4 a aviator's helmet which is part of the airborne communications system which will provide communications of high intelligibility under the extreme noise conditions encountered in military aircraft.

The preservation, packing and marking specified herein are intended for direct shipments to the Government. However, at the option of the contractor or when so specified, the packaging provisions herein are also applicable for the preparation of headset-microphone kits for shipment from the parts contractor to the original equipment manufacturer.