Columbian #10 Business Envelopes are a great all-purpose solution for mailing letter-sized business documents. Designed for everyday office use, these standard white envelopes are ideal for correspondence, invoices, statements, checks, and marketing materials. Measuring 4-1/8\" x 9-1/2\", they comfortably fit standard 8-1/2\" x 11\" sheets folded into thirds.\n\nEach self seal envelope is made from durable 24 lb white wove paper, offering a professional look that reflects well on businesses and schools. A blue security tint with an interior safety pattern helps block visibility through the paper, protecting sensitive information from being read during handling or delivery. The plain front, no window design provides flexibility for a wide range of mailing needs, from correspondence to promotional materials. The peel-and-press adhesive strip creates a strong, reliable seal without moisture, helping keep hands, desks, and mailroom workflows clean and efficient. Beyond mailing, these envelopes are also commonly used as cash budgeting envelopes for organizing spending categories, sinking funds, or savings systems at home or in small offices.\n\nPackaged with 500 envelopes per box, Columbian #10 Self Seal Envelopes are a dependable, never-out essential for offices, small businesses, and households that value security, convenience, and organization in their daily mailing tasks. (Manufacturer Item Number: COLO151)