In the late 1960s, the Singapore Armed Forces (SAF) adopted the AR-15 as their main service rifle.[citation needed] Due to difficulties in obtaining the rifles from the United States, the Singaporean government purchased a license to domestically manufacture the M16 rifle, which was then designated the M16S1. However, the domestic rifle requirements were not sufficient to allow Chartered Industries of Singapore (CIS, now Singapore Technologies Kinetics) to economically maintain operations at its rifle factory. Export sales of the M16S1 were not a viable option.