Hard blue Ferris wax in a block form for melting in a wax pot, or using a flame or electric waxing instrument. Similar to the wax used by advanced standing schools for wax application to preparation.
A large amount like this may be cut and shared by several students.
3.5″ x 3.0″ x 1.5″
Note: this is NOT the wax recommended for wax block carving exercises