Refractory materials are fabricated in two forms: shaped and unshaped (monolithic) refractories. Shaped refractories include fired and unfired materials with predetermined shapes, precast shapes and fusion cast refractories. Monolithic materials include plastic mixes, castables, ramming materials, dry vibratable, gunning materials, fettling materials, coatings and mortars. Monolithic materials differ from refractory bricks in that they are not shaped and fired before use. These materials do not have high energy requirements, are more readily available, take shorter times to install, can be repaired locally and require less manpower.