This is Mercury Tactical Gear, an American military and outdoor brand. I received it from a colleague who is retiring. Mercury Tactical Gear is a military gear brand with a track record of supplying the US military. They offer a wide range of durable tactical equipment, including backpacks, carry bags (sea bags), utility pouches, and system notebooks. In Japan, these items are often distributed as "surplus goods" from US military bases, such as those in Okinawa, and are popular among survival game (airsoft) enthusiasts and those who enjoy military fashion. ・Size Height: 50cm Width: 35cm Depth: 20cm Capacity: Approximately 35-50L *Please note that these measurements are approximate. It has been cleaned, but there is overall wear and tear. In particular, there are some scratches and stains on the outside of the backpack. Please check photos 19 and 20. There may be other overlooked stains. Please understand that this is a used item, and only purchase if you are comfortable with this. Instant purchase is welcome. I will ship it in a suitable size paper bag or cardboard box.