Letraset Instant Lettering
In the 1960s, putting together and printing a graphic product still required hugely expensive machines and the expertise of graphic designers and typographers. Transfers, meanwhile, only cost a few pence and did not require great technical skills to use. They were the first DIY graphic composition technology and, unsurprisingly, they were enormously successful... The ‘anarchic’, low-cost and unmediated nature of transfers made them very popular among the era’s counterculture movements. In some cases, employing a publisher or professional graphic designer would have increased the risk of whatever the creator had in mind being censored or not produced at all.
"Letraset's legendary transfers" by Giovanni Blandino for pixartprinting.co.uk