Exactly what it says. Top mount filament spool holder for Airwolf 3D v5.5 I got tired of losing prints at the end of tightly wrapped spools. Top feeding eliminates the problem. It's very sturdy, and fits perfectly onto the frame of the 5.5I printed in ABS 50% infill - honeycomb .3mm layer 3 perimeters 5 top and 5 bottom solid layers Remove the head of 1 sheet metal screw, sink it into the end of the rod, and you're done.