This really is wonderstuff! Sugru is like modeling clay when you take it from its pack. Once it's exposed to air, it cures to a tough flexible silicone overnight using the moisture in the air. Working time = 30 mins. Cure time = 24hrs. It can be used for mending, re-modelling, improving and personalising your things. When Sugru cures, it's flexible rather than rigid. Which means that you can repair things that need to be able to move like textiles, cables, or shoes. Sugru is designed to stick to as many other materials as possible. It forms a strong bond to aluminium, steel, ceramics, glass and other materials including plastics like perspex. Sugru is made from non-toxic materials and is safe for children to use. How does it come? Sugru packs contains 3 sachets (5g) of Sugru, one each in red, black & white. Each sachet is individually wrapped and should be used in its entirety once it's opened.