These are printable extensions to turn a standard 19 mm piece size 3x3x3 Rubik's cube into a Pocket Cube, an extended version of a "lines and quads" bandaged cube.
There are two versions included. The offset files include extensions that will entirely cover the cube, making all the surfaces the same material and color for either painting or in theory, a stickerless version. This comes at the cost of the small 2x2x2 section being slightly disproportionate. This should be somewhat visible in my example in the included images.
The Flush version does not use the thin caps, extending only where needed, and keeping the cube proportional. You will of course have to fill in crevices on exposed bandaged pieces. This is the version you'd likely use if you wanted to paint it black and sticker it afterwards.
OffsetCenterCap x 3
OffsetCornerCap x 3
OffsetEdgeCap x 6
OffsetCornerExt x 1
OffsetLineExt x 3
OffsetQuadExt x 3
FlushCornerExt x 1
FlushLineExt x 3
FlushQuadExt x 3
Due to slight variances in printer tolerances and cube sizes, I would recommend printing out one of the larger extension pieces and fitting it to your cube. If it seems to rub against other pieces as it turns, shrink all the models down a very small percentage (~1% or less).
You need supports only for the corner extensions. The rest can be printed flat one way or another.
I recommend gluing the bandaged pieces together before gluing on extensions for added durability and alignment.
The images included and those at the link here should give you a good idea of which pieces to glue together.