Daikin AC plenum intake / outtake for the FDXM25F9, FDXM35F9 (and maybe FDXM50F9 and FDXM60F9)
https://cad.onshape.com/documents/e8410d33bd6b0b8be7fdbea3/w/f4abbd62211379858183fc76/e/9d94a39d0c8581690e933a67?renderMode=0&uiState=65e7149f837eba5bc9534886
The author marked this model as their own original creation.