Pirastro Contrabass Strings Flexocor Deluxe Solo tuning (A.E.H.Fis). I purchased these used, having been strung for about six months, and have not used them. Contrabass strings are expensive, so if you understand that these are used strings and would like to try solo strings, I will offer them at a lower price. You could also use them for orchestra tuning (GDAE).