✅ PERFECT A3 FIT & PROFESSIONAL LOOK: A3 Manilla Hard Board Backed Envelopes ( 457mm x 324mm ), designed to hold A3 documents, certificates, photo prints, invitations, and cards without folding. Pre-printed with "Please Do Not Bend" for careful handling and a professional finish. Comes in a value pack of 10. ✅ RIGID HARD BOARD PROTECTION: Constructed with a 120gsm kraft paper front and 1000 micron hard board back, these envelopes prevent bending and creases, keeping your documents, photos, and artwork safe and intact during shipping. ✅ STRONG & SECURE SELF-SEAL CLOSURE: Features a 10mm wide, high-quality self-adhesive strip for quick, tamper-proof sealing — no need for tape or glue, keeping your contents safe and secure. ✅ LIGHTWEIGHT & COST-EFFECTIVE: Sturdy yet lightweight design helps save on postage costs. Easily write addresses directly on the envelope or attach sticky labels as needed. ✅ ECO-FRIENDLY & SUSTAINABLE: Made from 100% recycled, biodegradable, and plastic-free materials — an environmentally conscious choice for both businesses and personal use.