Very nice project "BEARTRAP" patch in excellent condition. Measures approximately 3.5 x 2.5 inches. 
 
The mission of Project BEARTRAP (CNO Project K-0416) is to gather magnetic and acoustic data in order to identify and track submarines. Magnetic data is collected using a magnetic anomaly detector while the acoustic data are measured by sonobuoys laid in a pre-defined pattern. BEARTRAP missions are flown by specially equipped P-3 maritime patrol aircraft and ship-based SH-60B LAMPS helicopters to gather acoustic sound pressure level information.