I just modified a Jonsered 2159 the other day using a Stihl 660 tank vent. The 660 vent is a round modern style vent with a hose barb formed onto it. Jred 2150/52/53, 2156/2159 and Husky 350/3, 346, 357, 359 are all basically the same vent. I gutted the stock vent completely, drilled a hole inside the tank behind where the vent goes and reinstalled the white vent nipple. Ran the hose to the top cover and put the 660 vent in the end of the hose. It works perfect, easily serviced, flows plenty and leaks no fuel. I have not tried it on the smaller saws so I don't know if there is enough room under the top cover for it or not but it works great on the bigger saws.