In this chartholder the back is a rigid light enameled metal plate. The clamp or clip is of heavy wire and has two contact points, but instead of relying on metal or small rubber tips at the contact points, as in those on the market, two rings come in contact with the back. Two upright pins about one inch high are set into the back over which the rings drop when the spring of the clamp is released. The record sheets, after padding, are perforated, at a very slight cost, by the printer at the proper place for the pins.
With such a holder the record sheets can only be released by exerting sufficient pressure to raise the ring of the clamp clear of the pin and lifting the sheets off the pin. No adjustment is required to keep the various sheets in alignment while the proper sequence of the