This 13.5" (35cm approx) diameter funnel is manufactured from heavy duty food grade plastic. It DOES NOT come with an integrated straining disk. It can be used for many jobs in home beer and wine making.
It is huge and large enough to sit across the rim of 25 litre buckets and 25ltr wine fermenter to make it easy to strain fairly large volumes of pulp from fruit wines. It will not fit into the neck of a standard 25mm diameter demijohn.