The Tekton 41-Piece Flat End Hex and Star L-Key Set includes 0.050–3/8 in. and 1.3–10 mm flat end hex L-keys, T6–T50 star L-keys, and holders. The keys are made with 8660 nickel chromium molybdenum steel that's heat-treated to HRC 54-58. The keys are coated with a durable manganese phosphate finish that's resistant to corrosion. With the exception of the smallest sizes, Tekton L-keys are marked in two ways—both with a high-visibility laser marking and a stamped marking (the 0.050 in. and 1.3 mm keys are too small to laser mark and the 0.050 in., 1/16 in., 5/64 in., 1.3 mm, 1.5 mm, and 2 mm keys are too small to stamp). The durable hex key holders have self-aligning key slots that allow keys to be removed and inserted without moving others out of the way.