This is a set of D'Addario "Prelude" 4-string bass strings for a double bass (contrabass). These strings were removed immediately from a brand new instrument and have been stored unused at home for about 2 years. There appears to be no discoloration or degradation due to aging. Although unused, the item is considered used, so the condition is listed as "no noticeable scratches or stains." D'Addario Prelude strings are well-regarded as all-around strings, and some people use them on upright basses and silent basses as well.