Studying how pinch flats occur and how tyre inserts interact with the tyre and the rim, Tubolight moved material right where it needs to be, over and outside of the rim bead. The portion over the rim bead is increased by 30% to 60% depending on rim width, and together with a harder compound, rim hits are drastically reduced. The super tight fitting is retained because that’s an incredible bonus for added lateral stability and avoiding tyre burp. The air channel between the insert and rim acts like a valve, during a shock, some of the air inside the tyre moves from the outer portion of the insert into the channel, causing a difference in pressure. As the insert is very tight on the rim, this air gets trapped and takes a fraction of time longer to re-establish even pressure between the outer and inner portion. That means, in the real world, rolling resistance and tyre rebound are reduced. These two features combined give what every rider is looking for: EFFICIENCY. Single – No Valves Designed for 2.35 to 2.8” tyres. Gravity / Ebike front and rear, Trail as a rear paired with SL only 90g in 29” NOTE - At first installation, Tubolight suggests not putting sealant in from the valve but in the tyre before fitting to the rim.