This product is a set of 5 "Koneko Bin 420" dedicated envelopes from Yamato Transport. * Thickness: 3cm * No weight limit * Nationwide flat rate: 420 yen (Shipping is free when using this dedicated envelope) ※ This is a new, unused product. ※ The envelopes will be folded in half for shipping. Please understand. I purchased these from an acquaintance, but I won't be using them, so I'm selling them. Thank you for your purchase.