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10 Security Self-Seal Envelopes,Windowless Business Mailing Envelopes ,Security Tint Pattern for Secure Mailing, Invoices and Statements , Size 4-1/8 x 9-1/2 Inch - White - 24 LB - 500 Count : Amazon.co.uk: Stationery & Office Supplies
TRIPLE PRIO DL White Peel and Seal Envelopes - Secure Self Seal No Window Design - Perfect for Home Office & Business Mails (25) : Amazon.co.uk: Stationery & Office Supplies