620 rear light bulb

[jayrus544]

Does anyone know what the number of bulb it uses the deere part number is ar21739r but I can't find a cross reference chart thanks

 

[Dan in Ohio]

You can get one from John Deere for $2.75. Drop the r from the end of the part number. See small lamp chart below.
Small lamp cross reference

 

[Bob]

(quoted from post at 14:45:22 11/18/19) Does anyone know what the number of bulb it uses the deere part number is ar21739r but I can't find a cross reference chart thanks

Your number, AR21739, isn't on Dan's chart, but it has been replaced by AR86969, which is on the chart and crosses to a "105" miniature lamp.