READ DESCRIPTION. IMPORTANT INFORMATION BELOW! This is an untested mold for a convergent divergent rocket nozzle. The side that attaches to the rocket has a radius of 7.5mm (diameter 15mm) so you can resize it to fit your rocket. The picture uploaded shows you where to cut the model so the mold can be removed after the nozzle dries. This is designed so you can use a mix of aluminum foil and resin glue to wrap around like paper mache. Remember not to put epoxy on the layer that comes in contact with the mold. KNO3 rocket fuel (Sugar and KNO3) is hot enough to burn through a few layers of aluminum foil (1 to 3) so remember to apply multiple layers if you want the nozzle to be reused. Do this at your own risk!