Clamping system on top of the blade to secure the handle to the blade. Screw from top of handle engages a opening in the blade allowing the handle to be pulled secure to the blade. Utilized on a No. 66 handsaw made by H.H. Woodrough reported at the 22d International Antique Tool and Sale Apr 2003. It is possible that H. H. Woodrough was a house brand of W & M.