This vintage item was recently re-installed onto our pews. They are usually referred to as "hat clips" or "button clips". They are made of brass or copper, are spring-loaded and say "Dennings" on them with several patent numbers. According to a recent Ebay posting on the internet of a similar item, these were probably manufactured in the early 1900's and invented to hold a man's hat during Mass.
As you know, we used a company that specializes in antique pew restoration to restore our church's original (125 year old!) pews. Of course they had to take the antique hat clips off during the refinishing process and we had to do some convincing to have them put back on! It was fitting to advocate to keep this little part of history from a bygone era, don't you agree?
We also have had combination envelope/pencil holders (these are new) installed in the pews at this same time. This is a neater looking solution to have offertory envelopes readily available for the many visitors that come to Mass on the weekends.
How can you help? The pew areas tend to "collect" old bulletins and programs. If you see anything that doesn't belong there or needs straightening up, please help by tidying up your pew on your way out!