By the end of the 1960s China was awash with hundreds of millions of little red books.
There were the Selected Works of Mao Tse-Tung*, Selected Readings from Mao Tse-Tung, Quotations from Chairman Mao Tse-Tung, the Newest or Latest Directives, and numerous other volumes of explanation and exposition - all of them pocket-sized and distinctively covered with red vinyl. Maozhang reflected this popular literacy; sometimes as miniature replicas, more often incorporating one or more little red books into the overall design.
* the Wade-Giles spelling is used here to conform to the titles printed on the book covers
When listing the economic achievements of the Cultural Revolution in January 1969, the PLA General Logistics Department proudly noted that one of their factories had, "...manufactured China's first combined automatic high-frequency heat-joiner, which allows for a fourfold increase in efficiency when producing covers for the "Treasured Red Books".
cited in China's Cultural Revolution, 1966-1969 - Not a Dinner Party, ed. M Schoenhals, p261