Scare by opening the Amazon package: blister mentions only Garmin GPS Colorado series. Ride on the Garmin website, and the carabiner is not listed in the Dakota accessories. Research 010-11022-00 reference, and again the Garmin website only cites Colorado ... All's well that ends well: the clip is perfectly compatible with my Dakota 20!
The set is well finished. The carabiner is very large compared to the GPS: it is larger than the screen. The webbing between the hook and the plastic clip is quite short, about 1cm. Like all accessories to clip the back of the Dakota, remove it to change the batteries or the microSD card. Too bad.