Since 2017, a few manufacturers have moved to the same standard: 3 screws spaced by 4cm : RRD, Takuma, Naish, Gong (55USD for 65cm mast), Airush … The mast is held by 3 screws diam 6mm, the fuselage is held by 2 x 6mm screws (could be 3). This profile is not symmetrical as profile max thickness is located at 40-45% from and closer to leading edge.
Seems that Chinese factories are offering these masts for a good price.
http://www.kiteforum.com/viewtopic.php?f=196&t=2399988
Other airfoil section has concave trailing edge, based on the Eppler 837 used by Manta, Zeeko, RL… ensuring a very low swirl.
