A slim case for AYIMA mini amplifier - for double TPA3116d2 version with BK3266 BT chip . See third photo for reference.
Has a cutout for radiator.
Connectors for power and speakers have to be desoldered - or an additional cutout needs to be added.
Board has provisions for soldering power and speakers directly - so i decided to just remove them.

Use 4 m3 heat-set inserts from top side and 4 M3*10 screws to fix the board.