These hex keys are all individually coloured in plastic sleeves which also have the label for the size. The sizes included in the set are 1.5mm, 2.0mm, 2.5mm, 3.0mm, 4.0mm, 5.0mm, 6.0mm 8.0 and 10mm. The smaller sized keys are have oversized shafts in order to add strength and ergonomics, with the 1.5mm for example having a shaft about 3mm in diameter, and smaller at the hex part. Each key has a ball-end that lets you use them at angles up to 25 degrees.