Used to obtain information about the shape and angularity of grains in the 0,063-4 mm fraction of aggregates. The efflux index of an aggregate is the required time in seconds of a known volume of aggregates to flow from a known opening.

The unit is basically formed by:

-Aluminium body, Ø90 mm by 125 mm height
-Aluminium feed hopper Ø100 mm by 170 mm height
-Control shutter
-Polycarbonate funnel having 85 mm height
-60° conical part, which end has Ø12 mm
-Base support
-Valve
-Decanter