Flash Technology evolved the Vanguard Medium FTS 370 for compliance with FAA AC 150/5345-43J (infrared obstruction lights). To comply with the AC, Flash made the following product changes:
- Redesigned the FH 370 core board
- Released a new marker, MKR 372 (L-810)
- Implemented use of a 3-conductor shielded cable with markers
- Released a new Marker Interface Board
- Released Marker Firmware V3.0 to support these changes