Interestingly enough, there were previous Explorer type models in existence prior to Rolex registering the trademark in January of 1953 after Sir Edmund Hillary and Tenzing Norgay climbed Mount Everest. Some design defining characteristics include a strong case and specially lubricated movement to function between certain temperatures as well as having an incredible legible dial. The architectural design simple yet distinct and versatile. The model has been designed to be highly reliable and accurate. Everest bands and accessories on this page fit the Explorer I 39mm (model 214270).