Pack It In

It's Tetris, but in 3 dimensions! Pack all the pieces into the box, so you can fully close the lid. Simple, right?
The puzzle supplied will be either black with red pieces, or red with black pieces, at random and depending on stock.
3D printed in house, originally designed by rarelyevil under the CC by-sa 3.0 license.
Size of box when closed: 45mm x 45mm x 25mm