| 16B6806 | U1725 | MINISTRY OF DEFENCE AIR DOMESTIC R FERENCE NUMBER USE ONLY |
| 17-27B | 99237 | AIRFORCE-NAVY AERONAUTICAL DESIGN STANDARD |
| R234P5 | K0640 | FREUDENBERG TECHNICAL PRODUCTS |
| R8725P5 | K0640 | FREUDENBERG TECHNICAL PRODUCTS |
| BS1806-442 | K7766 | BRITISH STANDARDS INSTITUTION |
| BSM48-442 | K7766 | BRITISH STANDARDS INSTITUTION |