Serial Number 018474
Flyer in Box: “How to Take Care of Your Slide Rule”, Back Cover Number: S14-3
Clark McCoy’s K&E Catalogs – 4053 Information page
Catalog Number: MHF-39, Location: MHF-D1
Keuffel & Esser 68 1643 (4153-1) 5″ Polyphase Mannheim with pocket clip