One size fits most. The blinking eyeball glasses is 7.09'' x 2.76'' / 18 x 7 cm. With the 2 adjustable straps, it fits the size for adults and children at all ages. Hilarious gag gifts and pranks for adults and kids. This googly eye glasses will blink as the wearer grins and stop. It is a novelty funny prank toy gift. With the 2 adjustable straps, it fits the size for adults and children at all ages. How to adjust the 2 straps. Step 1: There are 3 adjustable holes on the temples of glasses. Select a hole based on your face shape, pass through it with the white strap, and then tie the white straps tightly under your chin; step 2: Thread the black rope through the hole at the end of the temples of the glasses. Pay attention to correct bundling, as shown in the figure. These colorful eyes glasses are good gifts for families, children, couples, relatives, cousins, friends, classmates, colleagues, roommates. Have fun together. Perfect fancy dress up for costume parties, role-play party, beach party, hen night, stag night, Halloween, Christmas, birthday party, meeting, attend class, commencement, bachelor party, graduation party, wedding photos, photo booth props whether indoor or outdoor. Perfect party supplies.