Hi BT,

Found this while cleaning out the hangar. For sale, $55 includes USPS S&H to US address with insurance - New one is $80+ Worked with the legacy GNS430 & 530 in my BE58, ~4 yrs ago. Will ship once payment is received via Zelle or check. Spec's / pic below.

Compact and portable USB reader/writer (blue component only/data card not incl)
Compatible with Garmin 150/150XL, 155/155XL, 165, GNS 250/250XL, 255, GNC 300/300XL, GNS 400 & 500 series, and GNS 400&500 WAAS series (not compatible w/ the 480 unit)
Windows 7.0, XP, Vista compatible, both 32-bit and 64-bit installations are supported
Mac OS X v10.6 or later. 64-bit Intel processors only
Works with JDM (Jeppesen Distribution Manager) for NavData updates
USB 1.0, 1.1 and 2.0 compatible

DM if you have questions. Thank you.