Linking Notebook PC's to networks is made easier by a new computer gizmo.

Owners of more than 10 million laptop and notebook computers fill their electronic boxes but often need to unburden into local area networks when they come to rest.  Until recently these pocket-sized devices could be attached to a computer only with two screws that had to be alternately engaged and tightened, usually in a tight space. Sometimes, when tightened too much, the screw would snap off.
      

Now Xircom, in Calabasas, Calif., is selling adapters encircled by a belt. A user turns the belt to engage both screws at the same time. Resembling the tread of a Caterpillar tractor, the tread is soft and grabby on the outside and hard on the inside to mesh with the teeth of the screw heads.

Designed by Walter Raczynski, the tractor-belt adapter is built to slip when a screw is fully seated, preventing broken screws.

"The tractor drive is unique," says Steven Joe, marketing director for D-Link Systems, Irvine Calif., which makes connectors and other computer devices.

"It's very beautiful," says Marshall Behling, marketing director at Accton Technology, a connector maker in Fremont, Calif.

"People start right in playing with the belt," says Larry Plummer, Xircom's vice president for marketing.