To gain some perspective for my review of Leatherman's latest, the Charge XT and XTi, I rummaged through my tool bag and pulled out a couple of multi-tools from yesteryear. The two I found were an ancient Leatherman, so old that it has simply "Leatherman Tool" stamped on the side in block letters, and an early Gerber Multi-Plier with the retractable pliers head, circa the mid '90s.Both were state of the art in their day, but comparing them with the Charge Ti and XTi, two of the 23-year-old Leatherman Tool Group's latest offerings, is like comparing your grandmother's 17-inch, curved-screen CRT television with the latest high-definition plasma flat screen.By far the best feature of these new tools is the one-handed access to the knives. With the tool folded, a simple thumb movement unsheathes either the straight or serrated blade. I had always liked the original Gerber design, which allowed you to shake out the pliers with a flick of the wrist. But when I think of what tool I would most likely need in an emergency, when I might only have one hand free, the knife is my first choice. [Gerber now has the Legend, with one-handed knife access.]Once either of the Ti's blades is exposed, it locks into place. The locks contribute to the weight of the tool, however. At 8.3 oz, the Ti is heavier than both the original Leatherman (5.2 oz.) and the Gerber (7.4 oz.), neither of which had any locks. However, locking blades are a valuable safety feature and worth the additional ounces. The Ti's locking system is also quite ingenious, as the same thumb that extended the blade can trip the lock, enabling the knife to be put away as easily as it was extended.All told, the Ti has four blades: two knives, a saw (a multi-tool staple that I've always considered overkill), and a file. All are best accessed with the pliers folded. When the tool is unfolded, in addition to the pliers/wire cutters, there are the usual suspects: a large flat head screwdriver, a pair of scissors, a can opener, and two screwdrivers with interchangeable, double-ended bits. One is small enough to be used on eyeglasses; the other is a useful medium size. The bit sockets are spring-loaded; a simple tug removes the bit so it can be reversed, or swapped for any of the alternate bits available from Leatherman.Every single tool on the device locks. Releasing any of the interior tools, such as the scissors, involves pushing down on the locking mechanism on the inside of the pliers handles, a step up from previous locks, which required partially unfolding one of the other tools to release the lock.One last sweet feature on the Ti is the sheath, which can be mounted on your belt vertically, or horizontally. The former is the traditional method; the latter, while posing the potential risk that the tool could fall out of the sheath if the Velcro flap comes undone, prevents the tool from flopping around as much and is therefore more comfortable for sailors, like bowmen for example, who perform a lot of dynamic movements while wearing the tool.The only negative we could come up with is that the can opener on either Ti tool doesn't function well as a bottle opener. But then again, you can always use the opener on your key chain, your flip-flops, or your buddie's older, less tricked-out multi-tool.The Ti and the XTi, which has a third interchangeable screwdriver tool, both come with eight double-ended bits. Available starting 1/3/2007, $124, www.leatherman.com.