Quality Park, #6 3/4 Security Envelopes, Contemporary Seam, 500 per box (10412) #6 3/4 ENVELOPES: Perfect for sending a variety of things such as forms, checks, invoices, photos, etc. GUMMED FLAP: Provides users with ease of mind that their contents will stay securely closed within the security envelopes. PROFESSIONAL FINISH: Bright white 24lb wove paper makes for a fresh, clean appearance perfect for any use. SECURE: Interior blue tint will keep your contents safe from prying eyes, so you can ship fearlessly. GREAT VALUE: Every box comes with 500 gummed envelopes that are so versatile they can be used for multiple purposes.