About this 3D model

Monitor stand I created for my work desk. It's made to accommodate a 2mm-thick carbon fiber sheet. The sheet shown in the pictures is 400mm x 300mm x 2mm. The shelf surface is 8in off of the desk. Original document in Onshape: https://cad.onshape.com/documents/6983845158c0794934f41b03/w/78b191e026d682d4cb711734/e/78580d465c8126f368cecec1?renderMode=0&uiState=64c938f3fcbd1f5556bcd497