This Coded Lock made of Zinc Alloy and Adhesive which durable and strong. Its high security plastic covered cylinder to avoid dust and light weight for easily carry with your bike. And its 4 numbers design which easy to use and convenient. Feature - Color: Black. - Material: Zinc Alloy and Adhesive. - Size: 21.5x7.6x2.5cm. - EASY TO USE: So easy to use, your children can use the lock worrying or dealing with them losing the keys. This lock is so easy to use that we have found that quite a few customers use it as lock or even as container lock. - KEYS-FREE PROTECTION: Keep your bike or and secure without the need to carry keys that can be lost. The combination can only be set when the lock is open, as several of our customers wrote in answer to question. You can see their reply in the Questions and Answers below. - YOU DEFINE THE COMBINATION: Set a combination that is easy to remember with the resettable combination. - COMBINATION: Easily set your own 4 numbers by the fist use. Smooth dials turning gives you confidence for quality. - This U Lock is for bicycles, skateboards, sports equipment, gates and fences, grills and lawnmowers, tools, boxes ladders Scooters, Carriages, Mopeds, Motorcycles and so on. Package list: 1 x Coded Lock