Business Source BSN42251 No 10 Window Envelope 500 Box

Product Description

The BUSINESS SOURCE BSN42251 is a No 10 side-seam window envelope designed for standard business mailing applications. Measuring 4.125 inches by 9.5 inches, it is constructed from 24 lb paper in an oyster-white finish. The clear film-covered window allows recipient address visibility through the envelope face, eliminating the need for a separate outer label when using pre-printed or folded insert documents. Each box contains 500 envelopes packaged in an expandable corrugated box for convenient access and orderly storage on the shelf or at the workstation. Licensed mail-room staff, office administrators, and general business users typically handle installation of these envelopes into desktop or high-volume mailing systems.

These envelopes are suited for sending invoices, statements, checks, and other standard business documents that require a visible mailing address through a window panel. The No 10 format is the most common size for folded 8.5-inch by 11-inch document inserts using a standard tri-fold. The side-seam construction provides consistent flap adhesion and structural integrity during automated or hand-insertion workflows. The expandable corrugated box simplifies desktop storage and maintains envelope alignment during high-volume processing runs.

Key Features

• No 10 format: 4.125 inches by 9.5 inches fits standard tri-folded letter-size documents
• Clear film-covered window provides address visibility without an external label
• Side-seam construction supports both hand and automated insertion workflows
• 24 lb paper weight in oyster-white finish for a professional appearance
• Expandable corrugated box packaging keeps envelopes organized and accessible
• Box of 500 suits high-volume mailing operations

Compatibility

Designed as a standard No 10 window envelope compatible with typical desktop and commercial mailing equipment that accepts No 10 size envelopes.

Installation Notes

Load envelopes into mailing or inserting equipment according to the machine manufacturer's feed-tray specifications. Confirm window alignment with the address block of the insert before beginning a production run. Store unused envelopes in the original corrugated box away from moisture and direct heat to preserve paper quality and adhesive integrity.