Optimal mailer for applications or important documents

To send an optimum envelope to applications or other important documents with more than five A4 pages (unfolded). The quality is great and the price-performance ratio absolutely OK. Due to the increased rear wall of cardboard which documents can be sent special protection and thus arrive in a good condition as possible to the recipient.

Who needs frequently (large amounts) of these envelopes, which should consider to look at larger package sizes (z. B. with 250 envelopes), as they are expected to cover much cheaper.

For up to 5 leaves the format C4 would in my experience also sufficient.

The following is a brief overview of the most common envelope sizes:

Standard size (in my experience, ideal for up to 5 sheets):

DIN C6 = 114 x 162 mm (2 x folded sheet of A4 paper - postcard format)
DIN C5 = 162 x 229 mm (1 x folded sheet of A4 paper)
DIN C4 = 229 x 324 mm (unfolded A4 sheet)

Light oversize (in my experience, ideal for consignments of more than 5 sheets, for example, applications.):

DIN B6 = 125 x 176 mm (2 x folded sheet of A4 paper - postcard format)
B5 = 176 x 250 mm (1 x folded sheet of A4 paper)
B4 = 250 x 353 mm (unfolded A4 sheet)