Batman Helmet. Can be printed as is for larger printers. If printing for adult, recommended to cut and print in 2 halves. Set wall loops to 8 and layer height to 0.25. 

MAKE SURE TO SIZE PROPERLY. This is based off batman's head, not your own, meaning you should use your slicer to make it bigger/smaller and use the measuring tool. Note for the image I only included the top half in it.