My first model, a simple ceiling hook I made for hanging skis and other long stuff in the ceiling of my garage. Should be plenty strong to hang a lot heavier stuff, too. 

Dimensions roughly width 236 mm, height 181 mm. Mounting holes 80 mm apart center-to-center, diameter 6mm. FreeCad file included, feel free to change the dimensions as you see fit.

For mounting, make sure your ceiling material can handle the weight (and some more!) and use appropriate fasteners. Do NOT use countersunk screws without spacers! Spacers are also recommended to be used with non-countersunk screws to spread the stress evenly on a larger area around the screw hole. Pre-drill holes in the ceiling and use a short screwdriver to fasten the screws. Plenty of printable compact screwdriver models around, if missing one!

I printed mine with Jayo PETG, 6 layers on top and bottom, 4 perimeters, 25% gyroid infill and 0,20 mm layer height. Print flat on its side, no supports are needed.