Acupressure mat (sheet)

My take on an acupressure mat specifically designed for 3D-printing.

The tops of the spikes are flat with a diameter of approx. 0.8mm to make it easily printable but still pointy enough for the spikey feel! For the height and spacing of the spikes I used generic acupressure mats as a reference. Standing with one foot on a shaktimat and the other one on this acupressure mat makes hardly a noticable difference. With dimensions of 240 x 200 mm my feet (EUR 43) fit perfectly on it. For the back I would recommend printing 4-6 of them to have a surface of around 400 x 500-750 mm (which is pretty much the size of any generic acupressure mats but only costs around 4-6 $)

I highly recommend printing this acupressure mat in PETG with 0 top and 0 bottom layers but therefore 50-60% infill for the first two layers (base) and then 0% infill for the spikes. This way you are not only saving filament but also the mat is getting a very nice flex to it so it can be used on a pillow for the neck as well as on the floor for the feet or on an yoga-mat for the back. Since the spikes are pretty small there is no additional infill needed besides the two perimeters. 

Be aware that this is a real-life example for the well-known stringing tests (two or more pillars that get increasingly thinner with increasing height). So you should definetely check if your printer settings are dialed in to minimize stringing. Otherwise it will be quite the hassle to clean up afterwards.