Show Cause Notice waiver permits oral notice and payment to obtain closure of proceedings without penalty in non-fraud cases. An assessee may waive a written Show Cause Notice by written request and payment of tax/duty, interest and the reduced penalty, allowing oral notice and representation; the statutory payment window runs from department's receipt of the waiver letter, payments made before receipt are permitted, and in non-fraud cases payment of tax and interest before or within the prescribed period leads to no penalty and deemed conclusion of proceedings, which may be approved by an officer of rank equal to the adjudicating authority.