My version of the commonly referred to as Thai Massage Cubes. They come in slightly diffrent shapes - Block, Medium and Star. Blocks are 54mm peak to peak.
Each file has two split halves of a cube. Some assembly is required as you need to join them with glue. Alignment holes are included and uses a pair of short length of filament as alignment pins. Instructions included in the PDF file.
Print them all and find which suits you best.