Most sieves meet ASTM E11 or IS 565/3310-1 and are supplied with a certificate of manufacturing conformance. The standard 8″ sieve comes in either full height (2″ above the mesh) or half height (1″ above the mesh). Both are priced the same. The standard 12″ sieve comes in full height (3″ above the mesh), half height (2″ above the mesh), or intermediate height (1 5/8″ above the mesh), and are all priced the same. Please specify height when ordering. Back up cloths are available and provide support for fine mesh sieves and extends the life in wet-sieving operations.