Enhance your knowledge of electrical systems with this lot of 4 National Radio Institute (NRI) Electrical Training Books. These vintage manuals are perfect for enthusiasts and professionals alike who want to learn the ins and outs of electrical circuits and technology. Each book contains valuable information and step-by-step guides on electrical unit types and applications. With a unit quantity of 4, this lot is a rare find for collectors and those seeking to expand their technical knowledge. Made in the United States, these books are a testament to the quality of American craftsmanship during the heyday of the electronics industry. Add these manuals to your collection and get ready to dive into the fascinating world of electrical technology.