After watching a couple of demos’ on You Tube I’ve installed a product called ‘Ride-On’ puncture sealant into my new rear tyre.
It arrived the day after I ordered it by normal postage last week. Apparently, the sealant made for bikes and cars is identical (I checked by phone) so I ended up ordering the 16oz single bottle for cars, rather than the 8oz bottle for bikes....It cost me £11.96 which seems reasonable.
But looking at the 'bike' sealant in the videos below, it looks like it contains an orange dye, which would be easier to spot if you had a puncture, and also comes with the correct size valve-core removal tool.