These items were taken from an European parts lot.  I am not sure of the exact application for many of these items.  Questions welcome.  If you like to browse, and who doesn't, you can see all of these items by going to my eBay store (click on the blue door on the right hand side of the listing and then select "European Parts Lot"). Any additional information on this item follows.

NOT TESTED.  FOR REBUILD. Also, this dynamo is a 40 watt short model, the A10 used the 60 watt long model E3L.

Technically, due to its mounting end, it will fit any BSA twin, other than the 1,000cc v-twin made in '36-'38. It wont fit any singles that used a mag/dyno. Basically it was only correct for the models I mentioned. It would physically mount to any vert. twin BSA prior to alternator models, but as I said before, it would be only a 40 watt dynamo instead of a 60 watt model.