Features: Brand new and high quality Overall thickening and hardening, not easy to fracture: chromium vanadium steel, overall thickening and hardening. High quality vanadium steel forging: the surfaces of the wrench is polish and electroplated with chromium. Easy disassembly of screws: With high torques, it is not easy to slip or damage the nut. National standard opening usage specification: The wrench opening size refers to the tolerance specified in national standard T4389-2013, which is more standardized. High temperature quenching is sturdy and durable: High temperature tempering enhances toughness and prevents cracking. Dipped plastic handle provides a senses of grip: ergonomically designed to effectively reduce work fatigue.Clear printing of models: Multiple specifications are convenient to choose, beautiful and elegant. Widely applicable: suitable for various scenarios such as bicycles maintenance, car maintenance, mechanical maintenance, and home assembly; Multiple models and specifications are complete, making it easy to solve. Specifications: Material: Chromium vanadium steel Size: 6x7, 8x10, 9x11, 10x12, 11x13, 13x15, 13x16, 14x17, 16x18, 17x19, 18x21, 19x22, 22x24, 24x27, 27x30, 30x32 (optional) Package Includes: 1PC Double Sided Open End Wrench note: No retail package. Please allow 0-1cm error due to manual measurement. please make sure you do not mind before you bid. Due to the difference between different monitors, the picture may not reflect the actual color of the item. Thank you.