There are many different types of business models available for a business to choose from. The razor and blade business model has been around for over a century and is still one of the most successful types. It’s a simple concept: sell something cheap at first but make money by selling customers additional products and services down the road. Although the business model is over 100 years old, it is still a profitable one.
from StartUp Mindset https://startupmindset.com/understanding-the-razor-and-blade-business-model/