SISAK is a well established radiochemical technique used for studies of nuclides with half-lives down to ~ 1 s. The method is based on multistage solvent extraction steps applying specially designed centrifuges for fast phase separation. The equipment has been improved to gain access to even shorter half-lives, and to decrease the amount of liquid used. The new minisystem, SISAK 3, consists of a degassing unit to separate the gases from the liquid and of one to four centrifuges for rapid separation of the two phases after solvent extraction. The degasser and the centrifuges have volumes of about 0.1 and 0.3 ml, respectively. The liquid flow-rate per phase can be varied from about 0.1 ml/s up to about 3 ml/s, and the jet gas flow-rate from about 10 ml/s up to some hundred ml/s. The properties of the new system and its application to fast separations are briefly outlined.