This strap was specifically designed for the common Four E's Vortex Mixer MI0101002-14 accessory tray. However this strap will fit some other makes of vortex mixer trays as well.

The straps are designed to be printed in TPU.
 

There are two strap thicknesses to choose from:
2.35mm thick.
1.5mm thick.

The top strap is for holding items down as shown in the sample image. This strap is mounted to the main strap via the two oblong holes nearest to the center ring.