A blade is described. This blade includes a substrate having two surfaces that meet at a cutting edge of the blade. At a given location along a length of the cutting edge, the two surfaces are at an angle with respect to one another. Moreover, angles between the two surfaces are different at at least two locations along the length of the blade. In particular, the angles between the two surfaces may vary along the length of the blade. Furthermore, the blade may include islands having top surfaces positioned at other locations along the length of the blade. These islands may protrude above the cutting edge to protect skin of a user when the blade is used to cut hair. In addition, the islands may include fluidic channels that provide a fluid (such as air or a lubricant) at the top surfaces of the islands when the blade is used.