There is tyre called Amerityre which is made of hard polyurethane foam. They are therefore garenteed puncture proof. More on them here: http://www.puncture-proof-tyres.co.uk/ All the reviews of them I have read so far have been positive. They seem to be much better than a similar tyre called Green Tyre, though I had a pair of these on an old three speed roadster for around six months and had no problems at all.
There is tyre called Amerityre which is made of hard polyurethane foam. They are therefore garenteed puncture proof. More on them here: http://www.puncture-proof-tyres.co.uk/ All the reviews of them I have read so far have been positive. They seem to be much better than a similar tyre called Green Tyre, though I had a pair of these on an old three speed roadster for around six months and had no problems at all.