File:Vintage Hewlett-Packard Model HP-45 Advanced Scientific Pocket Calculator, HP's Third Handheld Electronic Calculator, Introduced in 1973 and Discontinued in 1976 (38772251491).jpg - Wikimedia Commons
DigiBarn Calculators: HP 45 in original case
Hewlett-Packard HP-45 Handheld Electronic Calculator | National Museum of American History
BetterZ 1 Set Green Axis Calculator Crisp Feel Rounded Texture Mathematical Calculations ABS 10-Digit Mechanical Key Calculator for School Beige - Walmart.com