Embryo Filter.

Embryo Filter.
The embryo recovery filter has a central column with a pore size of 75 micrometers. This permits the bowl to retain the embryo yet let the extra fluid drain off. The base of the column is impervious so there will always a 2 to 3 cm layer of flushing medium in the bowl which prevents the embryo(s) from drying out.

Ball BA (1987)