ZK246 built in 1972 - 1978 by Zaklady Radiowe Kasprzaka. It was the first polish stereo open reels tape recorder, pretending to the HiFi level. Two speeds (7.5 and 3.75 inches/sec), big (18 cm) reels, vertical and horizontal operation. During first years of the manufacturing, this very expensive device was almost unavailable. My device was not operating properly - keys required great effort. The next (1978) release was called M2404S - the devices differed by external appearance and slightly differrent tone controls.