To post a letter or package choose from different size envelopes which are suitable for the contents. Make sure your mailings arrive safely in padded ones that take the brunt of hits and bumps.
Popular standard sizes include A4, A5, C4, C5, and DL envelopes measuring 11x22 cm. For ease of use, choose packing with windows as a time-saving feature when sending bulk mailings. Instead of white, buy coloured and pearlescent mailers for personal and business use.