C5 Manilla String & Washer Gusset Window Envelopes (Qty 100) 229mm x 162mm x 25mm1 2 day delivery as standard on this product C5 Manilla String & Washer Window Gusset Envelopes. These manilla string & washer envelopes are C5 size 229mm x 162mm, so fits A5 size paper or half folded A4, with the added feature of expanding side 'gusset' for extra capacity in the envelope perfect for bulky items They feature a unique FULL WINDOW so you can see the contents inside and the string and washer fasten quite cool and retro, so a real talking