Puncture proof tyres that can be driven over nails are demonstrated at Herne Hill.
Herne Hill, London.
Several shots of cars with special puncture-proof tyres driving over bits of wood with several nails sticking out of them - the tyres are unaffected! A young boy holds onto a tyre while a man hammers nails into it and pulls one of them out. A tyre is bounced on the ground. Commentator explains that a new kind of liquid is inside the tube that automatically seals up any puncture the moment it is made. Various shots of the liquid being pumped into bicycle and car tyres; '- locfuite' (?) is written on one of the liquid containers.