18/02 Updated 165mm depth with extra sizes

Length size added. 150mm,175mm,200mm,225mm,250mm.

Description

Multiboard Flat Tray

Needed a tray to use on a multiboard, but all original multiboard tray are not flat, and the size are quite fixed.
Design a flat tray to hold the edifier speaker without extra space wasted.
Size of tray is 125mm by 165mm.

You will need to know what is needed to mount the tray. For this, all the other parts can be downloaded from the official multiboard
6x6 bracket [https://thangs.com/designer/Multiboard/3d-model/6x6%20MU%20Bracket%20-%20Bolt-Locked%20Inserts-999510](https://thangs.com/designer/Multiboard/3d-model/6x6%20MU%20Bracket%20-%20Bolt-Locked%20Inserts-999510)

Bracket-Fix Point Joint [https://thangs.com/designer/Multiboard/3d-model/Bracket-Fix%20Point%20Joint-1183172](https://thangs.com/designer/Multiboard/3d-model/Bracket-Fix%20Point%20Joint-1183172)

Small Thread - Fix Point [https://thangs.com/designer/Multiboard/3d-model/Small%20Thread%20-%20Fix%20Point%20%28Folded%29-1123334](https://thangs.com/designer/Multiboard/3d-model/Small%20Thread%20-%20Fix%20Point%20%28Folded%29-1123334)

If other sizes of tray are needed, will help to do with a little boost.