Most of us know that self adhesive hooks available in stores are pretty expensive things. With these hooks hanging pictures and other small items on a wall can be pretty cheap. 

Hooks can be printed without supports. To make them do the job you need to buy good quality double sided foam tape and attach it to the hook. I use strong Tesa tapes (typically available as 19mm wide, 1.5m long rolls).

The small hook with a tape area 19mm x 15mm should withstand 0.75kg max in ideal conditions (for tapes rated 50kg/1m) and the large hook should withstand 1.5kg max. We know that ideal conditions not always are the case so I would assume 0.5kg and 1kg max.

Please note:

• the hook's tape pocket width is 20mm to fit 19mm wide tape and please attach tape this way (vertically). It will give better results than other way around.
• make sure the surface you attach the hook to  is not dusty or greasy and clean it with alcohol if possible beforehand 
• the small part of the hook (that holds the weight) can come off if low quality filament is used or if a printer is set improperly. Strong layer adhesion is the key. Print with 100% infill.