Radford smoothing units. Passive C L C filters to give smoothish DC

Radford add on units with C L C passive filtering to give a good approximation to smooth dc from a raw rectified AC input. Will suit any bench supply. Free to good home. 15 or so available. West herts area
Now filed under B for bin. Space needed. Thanks for looking.
I guess the easy cheap availability of regulated DC supplies has made these superfluous.