Standard Business Envelopes #10 for Professional Office Mailing - Offices and accounting teams use these #10 window envelopes made from 24lb white paper that feeds smoothly through printers, supporting invoicing, vendor payments, and accounts payable workflows. Window Envelopes #10 with Single Left Window Alignment - Businesses mailing invoices, statements, and forms use these envelopes with a properly positioned left window, helping ensure addresses display correctly and reducing misalignment during bulk mailings.Professional Mailing For Business Documents - Offices mailing invoices, statements, and everyday business documents use these no. 10 left side window envelopes to keep documents organized and presentable during standard business mailings. weight: 6.03 pounds