For those who like to assemble traditional smokeless or black powder shotshells here is a component not seen in recent years.  The use of a hollowed out cushion wad to be used with a thin card separating it from the shot charge harkens back to the interwar years of shotshell deveopment.  The use of this type of felt "doughnut" wad to form an "air-cushion" intended to reduce pellet setback deformation, was discussed by Major Sir Gerald Burrard in his 1931 two volume work The Modern Shotgun.  

Lest you think this was back in the dark ages, it was in the 1930's that fold crimp factory loaded shotshells began to appear on the shelves of shooting sports emporiums.   

Of course if you are drawn to assemble such arcane cartridges, you will be forgiven if wearing tweed seems to be the most fashionable of hunting attire when afield.   

Oh yes, the felt wad noted in this discussion can be seen at link below:

http://www.ballisticproducts.com/12ga-CT2-1_4-Felt-Wad-per-500/productinfo/122CT2/

There yet remains a most interesting mystery in Ballistic Products' detailed description:

"SPECIAL PURPOSE FOR LAW ENFORCEMENT AND MILITARY: 12ga 1/4" Felt Wad with a "donut" cut in the middle for highly specialized loads. .760" outside diameter x .375" internal diameter."

http://www.ballisticproducts.com/12ga-CT2-1_4-Felt-Wad-per-500/productinfo/122CT2/