 ST Electronics is a company of ST Engineering which is listed on the Singapore Exchange.STET Homeland Security Services is one of the major security firms, such as Certis CISCO (the largest Auxiliary Police Force in Singapore having close to 4,000 armed officers), Aetos Security Management, Sinclair Knight Merz and Heierli Consulting Engineers, that are active in Singapore.It specializes in security consultancy and does not provide manpower.