36 Clock Keys. This is a new set of 36 clock keys. You receive: Three size 3 (3 mm) clock keys. Three size 4 (3.25 mm) clock keys. Three size 5 (3.50 mm) clock keys. Three size 6 (3.75 mm) clock keys. Three size 7 (4 mm) clock keys. Three size 8 (4.25 mm) clock keys. Three 1.60 mm clock keys. Three 1.65 mm clock keys. Three 1.70 mm clock keys. Three 1.85 mm clock keys. Three 1.90 mm clock keys. We work hard to update our descriptions and pictures of our merchandise. As part of a process of ongoing innovation by our suppliers, newer versions of the item shown may be shipped before we are able to complete an update. As a result there may be a slight variation in color and design.