Standard Horizon SSM-517A Earbud Microphone Standard Horizon SSM-517A Earbud Microphone Standard Horizon SSM-517A Earpiece Microphone. Compatible with HX210, HX280S, HX290,HX370S, HX380, HX40, HX400, HX851, HX870 and HX890. SKUSTXSSM517A MAN#SSM-517A ID#: 6752 Our Price: $39.95 Availability: In Stock Condition:Brand New Add to cart We’re sorry for the inconvenience, but please know we are working hard to replenish stock and fill backorders. Global shipping constraints and other material shortages have slowed the supply of products in many industries, including GPS and Marine electronics. We update the Estimated Shipping Date on our website in real time, so feel free to check back frequently. Thank You for your patience and for shopping with The GPS Store, Inc.