Columbian #10 Security Envelopes — 500 Pack White Self-Seal, 24 lb with Blue Security Tint

Columbian #10 Security Envelopes are 4-1/8 x 9-1/2" self-seal, no-window envelopes made from 24 lb white paper with a blue security tint for everyday secure mailing.

These envelopes are designed for routine business and personal mail: they fit a standard letter folded into thirds, close with a peel-and-press adhesive, and include an interior safety pattern that helps obscure contents from casual view. Packaged in a 500-count box, they balance professional presentation and cost-effective bulk supply for offices, schools, or home budgeting systems.

How do these envelopes protect confidential information?

Columbian envelopes include an interior blue security tint and printed safety pattern that reduce the chance of someone reading contents through the paper. The no-window design further prevents exposure of sensitive data, and the heavier 24 lb stock resists tearing during handling.

• Blue security tint and internal pattern block readability
• No window protects printed addresses and documents
• 24 lb paper adds durability and tearing resistance

How does the self-seal closure simplify mailing?

The peel-and-press adhesive strip closes quickly without moisture, saving time in high-volume mail tasks and avoiding the mess of licking or wetting flaps. The strong seal helps keep contents secure during transit and reduces rework for busy mailrooms.

• Peel-and-press release strip for fast closure
• Eliminates need for water or adhesive devices
• Reliable bond that stays closed in shipment

Will these envelopes fit my standard business letters and documents?

Yes — the #10 size (4-1/8 x 9-1/2") is the standard envelope for 8-1/2 x 11" paper folded into thirds. They accommodate invoices, statements, letters, checks, and many marketing inserts without awkward folding or trimming.

• Fits letter paper folded into thirds comfortably
• Works for invoices, statements, and correspondence
• No-window design gives flexibility for various inserts

How does buying a 500-pack help my office or home?

Purchasing a 500-count box reduces frequency of reordering and typically lowers per-envelope cost, ensuring you have a steady supply for regular mailings. Bulk packaging is convenient for organizations that process mail daily and for households using envelopes for budgeting or storage.

• Large quantity reduces downtime and reorder frequency
• Better value per envelope for high-volume users
• Ideal for offices, schools, and home organization systems

Who is this for? Columbian #10 Security Envelopes are aimed at anyone who sends routine mail and wants a professional, secure, and convenient envelope. They suit small businesses and corporate mailrooms that need dependable bulk supplies; schools and non-profits that handle invoices and notices; and households that use envelopes for budgeting, bill payment, or secure storage. If you need a standard, no-window envelope with a self-seal closure and an interior security tint, this 500-pack delivers dependable value and consistent performance.