Model for New Baseball Training Device

I’m looking to have a model made for a baseball training device called the Release Tunnel Trainer. It’s a small rectangular frame with an open center (a “tunnel”) that a pitcher throws a ball through to help with arm path and release. It should be lightweight, durable, and have soft padding on the inside. The width does not need to be adjustable. It’s used by two people—one holds it, and one pitches the ball through it.