Buchner Ring, to fit flask with 35mm neck internal diameter.
Durable, heavy-duty rubber buchner ring, designed for securely holding a buchner funnel in place when performing vacuum filtration. This is an off the shelf alternative to boring a large hole through a rubber bung. Will hold any standard size Buchner funnel in place.
This range comes in 5 different sizes (24mm, 35mm, 45mm, 60mm & 68mm) to fit the most common flask neck diameters.