$3.99
This is the digital STL file for a 3D printable Matte Box compatible with iPhones and other smart phones with similar camera arrangement.
The matte box Frame has a 38mm quick release base making it compatible with lots of tripods. it can hold 1 to 4 flags which can be adjusted to different angles to accommodate the ultra wide or Zoom cameras.
All parts can be printed without supports.
Additional parts needed: Rubber Band
See It In Action - https://youtu.be/X4cDLwysYk0