Orange Seal's Endurance sealant is really effective at sealing small and medium sized punctures.
Orange Seal claims its Endurance sealant can last up to 120 days before it dries out, which is about four times as long as its regular stuff and you only pay an extra £1 across all the sizes for this increased durability compared to the other best tyre sealants on the market. At £7 per wheel, only Muc Off’s sealant is more expensive but Orange Seal Endurance remained totally fluid in cold temperatures and easily sealed the 2.75mm and 5mm holes in our test tyre. The company claims it will seal slits up to 19mm and, while it did plug our 8mm cut, it was only temporary, when we added a bit of weight the tyre split open again. Like a lot of sealants, we reckon you’re just going to have to work it into the cut repeatedly and let it partially dry out if you’re trying to get going out on the trail.
We haven't noticed Orange Seal lasting significantly longer than most, but it does form into a protective skin on the inside of the casing, which is really effective at sealing small to medium size punctures.