Board Backed Envelopes Hard Please do not bend C3 C4 C5 C6 B4 B5 Cheapest
B4 / C4+ 352MM x 249MM. B5 / C5+ 238MM x 163MM. C4 - A4 ,324MM X 229MM. C5 - A5, 229MM X 162MM. Hard Board Backed Envelope - White / Manilla. 120gsm Kraft Paper Front 600gsm Back Board.