1) Tool for Sweeney Todd 
A straight razor is an old-fashioned razor with a blade that can fold up into its handle. They are also called open razors and cut-throat razors. Although straight razors were once the principal method of manual shaving, they have been largely overshadowed by the safety razor, which incorporates a disposable blade. Electric razors of various types...
[n] - a razor with a straight cutting edge enclosed in a case that forms a handle when the razor is opened for use
noun a razor with a straight cutting edge enclosed in a case that forms a handle when the razor is opened for use
a razor having a stiff blade made of steel that is hinged to a handle into which it folds.