It is best known for its resemblance to the Lewis Gun, having a similar gas-operated action and a barrel surrounded by a cooling shroud.

[note 1] The action was gas-operated, with the piston working in a cylinder beneath and integral with the barrel.

The cooling shroud could be removed without tools by unscrewing the front retaining ring from the barrel by hand.

The aluminium cooling fins inside were in two pieces and once the shroud was removed, came loose from the barrel.

A further wooden handgrip was provided ahead of the receiver, as the bare barrel would be too hot to hold, unlike the cooling shroud.