The answer is simple really. In a word it's "Overhead"! The amount of cost it takes to operate the business. In the OEM's case such as GE® with their Waukesha® engines and parts, they have enormous overhead with their facilities and employees etc... While we do incur a certain amount of overhead it is nowhere near the level the OEM has and therefore we can pass along savings to our customers. We often use the same factories that the OEM did or is currently using. GE does not manufacture all their parts in house, they have many factories they farm the work out to, and Workhorse Power does the same. Workhorse manufactures all their parts to meet or exceed the OEM specifications. Therefore you can get equal or better quality that fits, functions, and gets the job done for considerably less cost to you.