IMS Filter Baskets
The shape was created by I.M.S. to obtain the proper ratio between the base and height of the coffee puck in relation to capacity. The filter is cylindrical with a convex bottom to collect the coffee towards the center during percolation. This shape has been designed to exploit the whole coffee puck, which also facilitates drying and expulsion.
Best combined with bottomless portafilter holders.
To find out if the IMS Filter Baskets are compatible with your machine, check here.