170mm x 440mm White 350gsm Board Peel & Seal Envelopes (Qty 100)These 170mm x 440mm white board envelopes, made from sturdy 350gsm cardboard, are ideal for mailing items that need extra protection, such as calendars, certificates, artwork, or brochures. The durable cardboard construction ensures that contents remain flat and undamaged during transit. Featuring a convenient peel and seal closure, these envelopes provide a quick, secure seal without the hassle of moisture based sealing. Perfect for both business and