The 1964 US Mint Set Slab PCGS PR 67 PR 68 Red Penny Silver Set contains uncirculated silver coins with a fineness of 0.9, struck in proof quality at the Philadelphia Mint. Certified by PCGS, this set includes coins from the United States with a grade of PR 67, making them highly sought after by collectors for their pristine condition and historical significance. A valuable addition to any numismatic collection, these coins showcase the craftsmanship and design of the 1960s era.