This is a scanned and corrected version of a side fin from a Shapers river fin set. Size L, tabs fit in FCS slots. You can use it as a twin set or a replacement. Highly recommended to print from TPU 98A / 95A, not from any rigid material or TPU softer then this. The thicker version is thickened by 20% (only the shape of course, the tabs remained the right size ;)Print from TPU 98A, 100% infill, slow down to max 60 mm/s, layer thickness: 0,08-0,12