Wall fixture:

Attach with nails:
Function: fix your frames on the wall easily and inexpensively
Available with profile(s): square, round, rectangle
Tips: hammer the nails in and let them sink in 15 mm. A level tool will help you perfect your installation. Position the frame. Like indicated in the sketch, it can be used laterally at your convenience

Attached with adhesive:
Function: attach your frames on the wall in a non-permanent way (frames can be sticked many times)
Available with profile(s): rectangle
Tips: stick 2 or 4 blocks at the back of the frame, then remove the back transparent covering. Place on the wall, door or window. It can be moved many times by unsticking it from the wall (carefully if paint is old)

Attached with spacers:
Function: place your frames on the wall permanently and fashionably. Your display will seem to be floating in the air and can be changed very easily
Available with profile(s): square, round, rectangle
Tips: place your frame on the wall, then with help from a level tool and pencil, mark the place of the holes. Use a screwdriver to delicately screw the frame onto the spacers. Use of pins is optional, but it can make the display sturdier