Columbian White Gummed 4 1/8 x 9 1/2 Inch Double-Window Business Envelopes 500 Count (CO133) Envelope is designed to be compatible with most computer generated forms, invoices, purchase orders and more. Two Poly-Klear windows clearly show return and mailing addresses from contents eliminating the need to address envelope. Security tinted for added privacy and confidentiality. Side-seam construction. Premium 24lb white wove stock. Moisture activated gummed seal. Top Window: 1"h x 3-1/2"w, positioned 1/2" from left, 2-1/2" from bottom. Bottom window: 1-1/8"h x 4"w, positioned 1/2" from left, 3/4" from bottom. (#10) 4-1/8" x 9-1/2" 500 envelopes Envelope is designed to be compatible with most computer generated forms, invoices, purchase orders and more. Security tinted for added privacy and confidentiality. Side-seam construction. Premium 24lb white wove stock. Top Window: 1 x 3-1/2 Inches, positioned 1/2 Inch from left, 2-1/2 Inches from bottom. (#10) 4-1/8 x 9-1/2 Inches. 500 envelopes. Moisture activated gummed seal. Two Poly-Klear windows clearly show return and mailing addresses from contents eliminating the need to address envelope. White window envelope with a 24-lb. paper stock features a gummed closure. Envelope is security tinted and includes a bottom left window (3 1/2w x 1 1/4h) plus a top left window (4w x 1h). Double window allows the mailing and return address to show through. Diagonal seams work well with insertion and extraction equipment. Use for invoice processing. Privacy tint. Bottom window: 1-1/8 x 4 Inches, positioned 1/2 Inch from left, 3/4 Inch from bottom.