These Basildon Bond Envelopes are 95x143mm, 90gsm and come in a pack of 20.These envelopes are made from high quality paper and feature a distinctive watermark adding a touch of style. They feature a peel and seal closure making them easy to use and more hygienic than standard gummed envelopes and come in tear strip cellowrapping. These Basildon Bond Envelopes are perfect for letter writers who want to add a touch of class to their correspondence.. Duke (95x143mm) Envelopes. Pack of 20. Quality Paper: High quality 90gsm Watermarked Blue Envelopes . Peal & Seal Envelopes: Allowing the envelopes to be securely closed