[14 Length Optional] There are 14 length from 0.4 to 10mm adjustable. You dont need to buy many pieces guide combs for different sizes. Just own this one! Rotate the dial, then you be the most handsome guy![Easy to Use] Just need 3 steps for 5 seconds, the clipper guide comb . One: open the buckle back on the guide comb; Two:Put the head of trimmer into the top of guide comb; Three:Close the buckle.(If its loose, pelase check again if you have put the trimmer to the top of guide comb thoroughly)[Compatible Model] This length-adjustable guide comb is compatible for One Blade shaver QP2520 QP2530 QP2630.[Safe & ] This clipper guard is made of high-quality material, which is not only for long use but safe for your skin. The inner structure is tested repeatedly for precise length position.Colour:As ShownMaterial:plasticSize:14 Length Optional,0.4-10 MMPackage Contents:1 * Guide Comb GuardsOnly the above package content, other products are not included.Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.