ITG Air Filter JC20 & steel fitting plate 33JC20 to fit your 48/50 DCO/SP Weber. 
These filters can be used as a single unit or in pairs.

The picture shows the 40mm filter element & it is available in 25mm, 40mm, 65mm & 100mm.

These are internal heights. The width is 148mm, length(bottom) 186mm, length(top) 192mm.

The total height of each element is 50mm, 65mm, 90mm, 125mm, respectively.

The same element is used for many more applications with the base plate changed accordingly.