Best used for identifying groups and treatments. These bands can be easily marked on or numbered with All-Weather® Plastic Ear Tag Marker (C16290N) for temporary individual ID. For best results, use only an alcohol-based marker, wipe off area with alcohol, and retrace desired marking at least twice. Pre-numbered leg bands are recommended for a longer-lasting ID. 13-1/2 in. L. Made of 1-1/2 in. W ethylene vinyl acetate (EVA).