Plywood pliers, a glass hammer and a paper drill press are all In "Tools as Art IV" at the National Building Museum. It's a show of tools in art, from the collection of hardware magnate John Hechinger Sr.

Previous shows in the series have featured serious art - by such figures as photographer Berenice Abbott and pop artist Claes Oldenburg - but they've also been a lot of fun.

The National Building Museum is at 401 F St. N.W., Washington. It is open 10 a.m. to 5 p.m. Mondays through Saturdays and noon to 5 p.m. Sundays. "Tools as Art IV" continues through Feb. 7. For information call 202-272-2448.