2 PCS Breather Hose Gas Fuel Tank Cap, CNC One Way Tank Vent Tube with Aluminum Breather Valve, Universal for ATV Quad Off-Road Pit Dirt Bike, Motorcycle Accessories (Black)

They function well. I have replaced the black hose with clear Tygon tubing so I can see if the tank is boiling. They need replacing once a year, the check ball will corrode inside (the vent is aluminum but the check ball is steel.) Once the check ball in these vents corrodes, they will seize closed, and starve the gravity fed carb of fuel, or they will stick open and dump fuel when the bike is laying down. So annual replacement is prudent.

We used these to replace the rubber lines we were using to vent the fuel tank on two of our 4 wheelers. Inexpensive and exactly what we needed. Great fit, great quality.

I have a Husqvarna 701 Enduro that I have kitted out for mountain road/trail riding. One of the upgrades is an under-seat aux fuel tank of 1.5 gallons. It has (had) a breather tube with a valve on the end of it. Common for plastic aftermarket fuel tanks.Amazon has many many of them and I have ordered some that match the color of my bikes (like Kawasaki Green, for example).But the 701's vent tube was black and was very tenacious - it is right in the way of the ignition switch and it gets hit all the time. I finally lost it.So my quest was to find one that was black with silver rings and the tube would fit tight. Once I got these, I found they fit the bill. It is tight and looks exactly like the one that came with it...

I've bought numerous vents over the past years for the various ATVs I own and service.I've had to return or toss a number of the "cheap" vents I've bought through here.Some vents didn't have the internal check ball or simply leaked badly when upended.Both of these vents have a good check ball and do not leak when tested.I'll be buying this brand in the future over the others I've tried already.