a closure system including a polymeric split ring clamp and a polymeric lid for a polymeric drum . to maintain the integrity of the closure , the lid rim region is formed having an annular restraining notch which cooperates with twist inhibiting blocking components formed within the interior of a cooperating inwardly opening polymeric split ring clamp . the blocking component may be provided as a sequence of regularly spaced block - like protuberances located within the inward upwardly disposed region of the ring clamp . a secondary closure arrangement is provided with the split ring clamp which receives a polymeric banding strap to prevent one end of the split ring from disengaging with an associated pivot arm . when the split ring clamp is in a fully open or pre - clamping mode orientation , a capture groove is formed with the ring pivot shaft formed at one end of the split ring clamp . this capture groove is aligned with and engages a corresponding capturing pawl formed at the opening of the ring pivot shaft receiving notch . to facilitate cleaning and re - use , a polymeric gasket is provided which is removably insertable within a seal retainer cavity located at the rim of the lid .