SELF SEAL ENVELOPE- Just peel and stick 4 1/8 in. x 9 1/2 in size envelop. 500 units of number 10 SECURITY TINTED SELF SEAL ENVELOPES – Standard #10 envelope ( 4 1/8 x 9 1/2). HIGH-QUALITY 24lb. CAN’T SEE THROUGH ENVELOPES – Security printing pattern on the inside prevents from seeing what inside.