Ideal for mailing bulky items such as catalogues, reports, brochures and more, these New Guardian envelopes feature an expanding 25mm gusset and durable, heavyweight 130gsm paper. The manilla envelopes feature a convenient address window and a simple peel and seal closure with Power-Tac adhesion for a quick, strong seal. Suitable for A4 documents, this pack contains 100 C4 envelopes.