The Tri-Star measures 19 x 13 x 8" (480 x 330 x 205mm), putting it between the Western Flyer and the Aeronaut in size. It's a perfect size carry-on for use in Europe and Australia, where airlines carry-on sizing requirements are more conservative than in the United States. The size of the Tristar also works well for travellers who find that they don't need a carry-on as large as the Aeronaut, but can't or don't want to limit their packling list enough to use our smaller Western Flyer.

The front of the Tri-Star features four zippered pockets, all zipping shut with #8 YKK splash-proof Uretek zippers.

On the right is a subtle-but-clever curved zipper pocket: unzip it partially and it's a useful pocket for a boarding pass. Unzipped entirely, it's an expandable water bottle pocket. The bellows that make the pocket expandable can be snapped up so that your water bottle doesn't fall out, or unsnapped to allow greater access to the pocket. (Note that with a water bottle in the pocket, the bag may no longer meet the most strict size regulations: we assume that you'll remove your water bottle as you board the plane.)

On the left side are three horizontal zippered pockets. The top zippered pocket spans the full height of the bag; the second goes about half way; and the third is the shallowest of the three. All three horizontal zippered pockets have one "o-ring" inside for a Key Strap (one 8" Key Strap is included with the Tri-Star), Guardian Light or Clear, Padded, Cork, or Cordura Organizer Pouches, or a Clear Organizer Wallet. The big pocket can hold a New York Times Bestseller (even a hardback) or Kindle. The middle pocket can fit sunglasses or a laptop power supply. The small pocket can help keep your wallet, keys, passport, and other smaller items handy. The lower left-hand corner features the distinctive TOM BIHN Tri-Star logo label. Black piping boardering the front panel of the Tri-Star gives it a finished appearance and helps it retain its shape and size - no matter how much stuff you put in it.

The Tri-Star has three main compartments of approximately equal size. The front compartment can be further divided left and right, with a zip out divider. Depending on what you pack and how you like to organize, you may find this divider quite useful. Once divided, one side is larger than the other: the larger side can accomodate a three-ring binder, the smaller side handles a pair of shoes (inside a Packing Cube or not, your choice).

The middle compartment has two "Annex clips" designed to secure the optional Brain Cell laptop case to the Tri-Star; the Annex Clips are removable, so if you don't plan to carry a Brain Cell, you can remove them. The Brain Cell provides superior laptop protection with a corrugated plastic insert, a soft, brushed-foam interior, suspension system, and memory foam bottom - and still comes at just about 1lb for the larger sizes. In the Tri-Star, the level of laptop protection is increased because the Brain Cell sits between the other two main compartments. The Brain Cell can be unclipped from the Tri-Star and used on its own (it has handles and shoulder strap attachment points) or clipped inside of another TOM BIHN bag, depending on its size.

The back compartment is full of open space and is ready to accept one Large Tri-Star Packing Cube, a Small and a Medium Tri-Star Packing Cube, or your clothes just on their own. (This depends on how you like to pack: some people don't need or want Packing Cubes, while others would never travel without them.) The back compartment of the Tri-Star also features two compression/tie-down straps to help you keep clothing in place and wrinkle-free. It's an alternative to Packing Cubes. The compression/tie-down straps are removable (via Gatekeepers) so if you don't want or need to use them, you can leave them behind. The Tri-Star Packing Cubes are available for order separately by clicking here; they are available in Large (Fabric/Mesh), Medium (Fabric/Mesh), and Small (Fabric/Fabric or Fabric/Mesh).

Also available are the dual-purpose Packing Cube Shoulder Bag and Packing Cube Backpack (Tri-Star/Western Flyer). In preparation for and during your journey, use them to organize and pack your clothing. When you reach your destination and it's time to leave the Tri-Star at your hotel or hostel, re-pack the Packing Cube Shoulder Bag with a light jacket, wallet, lunch or small water bottle, map, and add a shoulder strap: you're ready to go out and explore, and you've saved space by not having to bring a separate bag for day use.

Each of the three main compartments of the Tri-Star feature two "o-rings". Additional and optional Key Straps, 3D Clear Organizer Cube (designed to serve as a 3-1-1 liquids bag), Guardian Light, Clear Organizer Wallet, and Clear, Padded, Cork, and Cordura Organizer Pouches can be affixed to the "o-rings".

The Tri-Star is made with an exterior of urethane coated, 1050 denier U.S. Made ballistic nylon (not 1680 ballistic nylon, which is not as abrasian-resistant as 1050) and lined with ultra-light Dyneema/nylon rip-stop fabric. We choose to use ballistic nylon over Cordura as an exterior fabric: we believe 1050 denier ballistic nylon is superior for travel as its smooth texture allows you to more easily stow and retrieve it from overhead compartments. 1050 denier ballistic nylon also naturally attracts less fuzz/pet hair than Cordura. Our 1050 denier ballistic nylon is custom-dyed for us in the United States. Our Dyneema/nylon rip-stop is the lining fabric of choice as it's ultra-lightweight (every ounce counts in one-bag travel) yet extremely tough. Our Dyneema/nylon fabric is custom-made for us in Japan in two colors: Steel Grey and Solar Yellow. If you prefer a brighter interior that helps you see inside a bag, you may prefer Solar. As with many TOM BIHN bags, we use YKK splash-proof Uretek zippers. These zippers keep the weather outside where it belongs. All of our fabrics are treated to be water-resistant: you may choose to renew that resistance with Nikwax every six months to a year, depending on your use of the bag.

The attachment points for an optional shoulder strap are off-set on the Tri-Star to provide the best balance and comfort should you carry the bag with a shoulder strap. We recommend using the Absolute Shoulder Strap with the Tristar if comfort is your primary concern. The TerraGrip Shoulder Strap is also a nice strap that focuses mainly on grip. You, of course, have the option of using any shoulder strap you already have that attaches to "d-rings". The two Poron-foam padded handles of the Tri-Star are positioned for maximum comfort, stability, and balance - they are designed not just to meet at the top dead center of the bag, but kiss there too, so no fishing for the second handle. Grab both handles, and your Tri-Star is a balanced load.

Empty, the Tri-Star stands up on its own. Depending on how you pack it, it will continue to stand up on its own.

The Tri-Star comes with metal zipper pulls. Included with the bag is a package of Cord Zipper Pulls (the pictures of the Tri-Star show the bag with these Cord Zipper Pulls as opposed to metal zipper pulls> so you can choose whether you want the bag to have metal or Cord zipper pulls. If you prefer the quieter Cord Zipper Pulls, you can cut off the metal zipper pulls and replace them with Cord Zipper Pulls. For instructions on how to do that, visit the Cord Zipper Pulls page.

The back of the Tri-Star features hide-away backpack straps. Want to carry the bag as a briefcase or shoulder bag, or stow it in the overhead compartment for a flight? Unsnap the bottom of the backpack straps and tuck them into the back compartment - you'll never know they were there. To turn it into a backpack, simply reverse these steps. The backpack straps are padded and contoured, and feature a removable sternum strap and a optional removable waist strap. Both the sternum and waist straps are simple webbing straps designed to help distribute weight and stabilize the bag to your body.