Astatic and diamond brands needle N281. Diamond  for dual cartridges CDS-310, -320, -520, -521, all -/3 and -/34, replacing dual needle DN34. Also, replacing Astatic N281sd, Duotone 826D/S, Electro-Voice 2501DS, Fidelitone AC-281D1, Jensen DU-13XSD, Pfanstiehl 301-DS73, Recoton 526SD, Transcriber PS-41 and Walco W-123STDS cartridges.