Machine doubling. Shelf like and flat with no notching the edges of the devices. Happens a lot of the larger coinage. Finding one without if is sometimes a challenge.
Although a very minor example, (Only one I have of a DDR in the Kennedy series on my server) here is what to look for when I mention notching:

A few Obverse doubled/tripled dies to see the hub doubling/tripling:
https://www.coincommunity.com/forum...964_D_DO.jpg
https://www.coincommunity.com/forum...64_D_TDO.jpg
https://www.coincommunity.com/forum.../1966_DO.jpg
Although a very minor example, (Only one I have of a DDR in the Kennedy series on my server) here is what to look for when I mention notching:

A few Obverse doubled/tripled dies to see the hub doubling/tripling:
https://www.coincommunity.com/forum...964_D_DO.jpg
https://www.coincommunity.com/forum...64_D_TDO.jpg
https://www.coincommunity.com/forum.../1966_DO.jpg






















