Nikon Speedlight Double Head Mount

Mount two Nikon SB910 or SB900 Speed Lights close to the centre axis of your umbrella or soft box light modifier.

This mounting allows Nikon Strobist photographers to double their flash output by mounting two Nikon SB900 or SB910 Speed Lights side by side.
The strobes are attached to the mount at their heads so that when using an umbrella style light modifier the heads are much closer to the centre axis and so enable a more efficient use of the light modifier.

To finish, press a 1/4" nut into the hex cavity between the heads.
Pair it with an  Umbrella Spigot and you're good to go.