From Square shooter. I haven't seen a two fletched atlatl, but the spear I made has two, compared to three
Fletches. Manards sells or used to sell a rod with a ball on top, made of aprox 3/4" steel tube.
It has a base made of a tube with four fins, designed, I suspect, to be driven into the ground. Now when I saw the base, I thought "spear trade head !¡" Sharpening each fin and mounting on a specially
painted up hickory sapling with feather fletching builds a spear to use with an atlatl.