Those sort of standard airline ballbearing couplings and they practically free-spin. Rotation is indeed an issue sometimes. There’s some resistance, but a few very heavy toys and particularly those heavy ones with an aggressive curve (medium Bad Dragon Crackers) want to flip over sometimes.
From 2019, Dao Huan Sex Machine hard lock system had upgraded, we added steel balls inside the female adapter, and all quick connectors added hollow design. The hollow align with the steel ball, will be locked by the steel balls inside female adapter. New quick connect system is designed for non-spin thrusting, extremely steady, keep toys in position when running at high speed – say no to the rotation.