When extruded, reacts with humidity in the air, curing inwards from the surface and becoming silicone rubber. Has outstanding adhesion to glass, ceramic, aluminium, and many plastics. Resists sunlight, weathering, water, and most chemicals. An excellent insulator, its dielectric strength is unaffected by electrical cycling or stress. Uses include potting electronic components, insulating electrical boxes, fabricating and repairing gaskets, and making expansion and contraction seals in bridges and tunnels. It is also used for general maintenance, caulking and sealing, and for production bonding. Available in 100 grm and 350 grm weight tubes.