Swiss Air Force modified, white, punched American NAF1092 leather flying helmet with (USN) TH-37 receivers, including an adapter with a USAAF plug. The pilot is also wearing a Pilotenkombi, an A-14 oxygen mask and American Optical sunglasses.

Swiss Air Force modified, white, punched German Siemens leather flying helmet with American ANB-H-1 receivers and headset covers. The pilot is also wearing a Zellweger laryngophone. Note the adapter cable for the radio communication equipment.

The holes and the white paint were a Swiss modification to reduce the heat under the P-51D Mustang bubble canopy.

Swiss Air Force modified, punched American A-11 intermediate leather flying helmet with ANB-H-1 receivers and a modified chinstrap. The pilot is equipped with a T-30S laryngophone. 

Swiss Air Force modified, punched American A-11 intermediate leather flying helmet with ANB-H-1 receivers and original Bennet buckle chinstrap. 

Swiss Air Force modified, white, punched American A-11 intermediate leather flying helmet with ANB-H-1 receivers and original Bennet buckle chinstrap.