Fishman ACC-V20-0JA Jack, 1/4” Carpenter Jack For ViolinA direct replacement for the jack provided with the Fishman V 200 and V 300 violin pickups. This jack, designed by Fred Carpenter, accepts a standard 1 4 instrument cable. It can also be left on the instrument and closed in many violin cases. If using with mandolin or viola, the user would want to additionally purchase the longer turnbuckles (available separately) for those applications.