20mm Ball Mount Adapter Socket, AMPS 30x38mm

This is a 20 mm socket-style mount built on the AMPS 30 × 38 mm base pattern. Many mobile-electronics and vehicle-accessory systems—phone mounts, radios, tablet holders, off-road accessories, camera brackets, and small control displays—use the 20 mm ball-and-socket standard along with the AMPS mounting pattern.

According to Chat-GPG, brands that use 20mm components include Bulletpoint, 67 Designs, Expedition Essentials, Tackform,  and Mob Armor.  There may also be MagSafe-compatible mounts available that use the 20 mm ball standard, particularly in off-road and truck-focused setups.  Note that this this 20mm component does not fit 1-inch ball sizes used in some brands.
 

You can mate my 20 mm ball plate with  this socket plate to form a swivel connection between two AMPS-compatible components—such as a mounting bracket and a phone, tablet, or accessory holder.

Also see:

17mm Ball Mount Adapter Socket

1" Ball Mount Adapter Socket

See my  Vehicle Mounting Parts Collection for additional related components.

It seems quite strong, even though it is printed vertically. Given the nature of a swivel joint, there typically isn’t much sustained lateral torque applied to the part.

Bambu Lab PETG HF has performed the best for me, producing very smooth threads and a firm, consistent friction.  Matte PETG and matte PCTG materials performed better than glossy variants. 

The print profile includes a versions with and without nut traps/inserts.  I have not needed supports.