When you actually hold this, it feels surprisingly sturdy and solid for its compact size! Plus, you can freely set your own PIN. The "U" part is connected on one side (Image ②). Inner dimensions of the loop: 14cm (height) x 4.5cm (width) Weight: Approximately 380 grams Thickness: 1.2cm Material: Steel Manufacturer: SAIKO (斉工舎) ※ This item is for bicycles. Please note that it may be too narrow for the wheels of scooters or other vehicles. ※ Please be aware that there may be some minor dirt, scratches, or discoloration. ※ Price is not negotiable. Since there are no instructions for setting the dial, please use Image ④ or the following instructions instead. The initial setting is 【0000】. Release the lock with the side PUSH button to open it as shown in Image ②. Rotate the part in Image ③ 180° in the direction of the arrow, then turn the 4-digit dial to your desired number. Return it 180° to its original position and lock it to set the code. Suitable for general bicycles (city bikes/lightweight bikes/school bikes), children's bikes (toddler bikes), fashion cycles, city cycles, MTBs, junior mountain bikes (CTB), cross bikes, road bikes, pist bikes, small-wheeled bikes, folding bikes, and electric bicycles. Also widely usable for security on handcarts, gates, entrances, and doors!