The NRI Correspondence Study Courses on Gunsmithing Booklets are a series of textbooks in English authored by various authors. These booklets are designed for vocational school level education, focusing on gunsmithing proficiency. The courses are published by NRI Gunsmithing Courses in the United States, providing students with comprehensive instruction on gunsmithing techniques and theory. With a focus on practical skills and knowledge, these booklets are a valuable resource for individuals looking to enhance their expertise in the field of gunsmithing. Preowned. Quizzes have answers marked. Still great reference material. Circa 1994. Originally course cost $1027 Ask questions before purchasing. Will be shipped USPS.