Silvine Blue Writing Envelopes - Pack of 20 - Size 90mm x 185mm (3.5 X 7.3) These good quality Silvine Writing envelopes are made in the UK These envelopes have a finished size of 90mm x 185mm (3.5' x 7.3') Comes in a pack of 20 Gummed envelopes and ready to use. Great for all your postal needs.