Compatible Units:

New Generation Garmin Units

Handheld models – Astro, Dakota, Colorado, Oregon (all models), Montana (all models including the new 700 and 750), GPSMAP 62, GPSMAP 64, GPSMAP 65, GPSMAP 66, GPSMAP 67, GPSMAP 78,  eTrex 20/30/22/32, eTrex Touch, Rino 600/650, Rino 700/750, Monterra.
Nuvi models – Nuvi 40LM, 50LM, 60LM and any Nuvi with four numbers in the model name. Example: Nuvi 1100, Nuvi 1490, Nuvi 3790. Drivesmart models.

Older Generation Garmin Units

eTrex models – Legend Cx, Legend HCx, Venture Cx, Vista Cx, Vista HCx
Other handheld models – 60 Cx, 60 CSx, 76 Cx, 76CSx, Rino 520 HCx, Rino 530 HCx