Seller: joawar (2,586) 99.9% , Location: Troy, Maine, Ships to: US & many other countries, Item: 182251393762 Vintage Box of Zinc Chromate Pan Head Self Tapping Screws in Original Box. Zinc Chromate coated screws were an early form of galvanization before hot dipped galvanizing came along. They are 2 1/2" No. 10 Type A Tapping Screws from 50 years ago. Originally had 100 screws in the box, there are 94 now. Made by The Whitney Screw Corporation Nashua, N.H. These are truly vintage screws that were used by my carpenter father back in the 1950-60's. Whether you're a Collector or a Builder in need, these Vintage Zinc Chromate Tapping Screws are for you. Thanks for looking...and while you're here be sure to check out my other items and add me to your favorites list!