VARIETY PACK: One package includes 12 pairs of medium and sixteen pairs of large picture hanging strips; four pairs of medium strips holds 12 pounds with max frame of 18 x 24; four pairs of large strips holds 16 pounds with max frame of 24 x 36WORKS ON A VARIETY OF SMOOTH SURFACES: Wall hanging strips work on a variety of smooth surfaces, including painted walls, finished wood, painted concrete cinder blocks, laminate, glass, metal and tilesSURFACE PREP: Clean the desired surface with rubbing alcohol to remove grime and dust to allow the wall hangers to bond to the surface; the indoor temperature must be between 50 degrees Fahrenheit and 105 degrees FahrenheitUSAGE TIPS: Wait seven days after painting before using the Command Picture Hanger Strips to allow paint to cure; do not hang over beds or on wallpaper; do not use the wall hanging strips to hang valuable itemsEASY CLEAN REMOVAL: Lightly hold the top of the wall adhesive strips and slowly pull straight down towards the floor to remove and prevent damage of walls and surfacesDAMAGE FREE HANGING: Wall hanger strips work without leaving holes, marks or sticky residue on a variety of surfaces and remove cleanly when you want to redecorate or reorganize your space without toolsWHAT TO HANG: Use these wall hanging strips to hang picture frames, college dorm decor, wooden letters, nursery decor, calendars or even to create a gallery wall