This is an ET Series replacement soldering tip for the Weller WE1010 soldering station. It is a "screwdriver" type of soldering tip, measuring 1/16" (1.6mm) wide. Replacing the tip is a breeze --- simply unscrew the currently attached tip, slip the replacement tip in, and screw it into place.
This Weller tip has been pre-tinned with a lead-free alloy. Although this soldering tip is called a "screwdriver," this is in name only and functions in no way similar to the tool it is named after.