Way, way below dealer cost closeout! The ring is used to attach a digital camera to the Digital Camera Adapter. This ring is for 37mm size cameras that include the Sony DSC-S50, S30, Sony Camcorders DCR-TRV series, DCR-PC100, TR290PK, Victor Camcorders GR-DVL7, GR-DVL700, Sharp Camcorders VL-PD7, VL-MR1