Our M3 Expandable Capacity Mailers measure 282 x 205 x 70mm and are almost identical to the cardboard envelopes you receive from Amazon, simply with a plain printed outer. These versatile corrugated cardboard envelopes have been consciously designed using eco-friendly materials, offering expandable space to accommodate a variety of items such as books and electronics while ensuring their safety in transit. User-friendly and environmentally conscious, these cardboard envelopes are the ideal choice for businesses committed to reducing their environmental impact without compromising on quality or functionality.