| 1951 | Spray Bottle Body | |
| 1952 | Spray Bottle Head | |
| 1953 | SeoJin Instech Level Controller SLA-4P / SMA-4P | |
| 1954 | SeoJin Instech Level Controller SQ-2U/4U | |
| 1955 | SeoJin Instech Level Controller SLC-100U / SLCA-HL | |
| 1956 | SeoJin Instech Level Controller SEC 3U/5U | |
| 1957 | SeoJin Instech Level Controller SLIC-4P | |
| 1958 | SeoJin Instech Level Controller SLI-100U | |
| 1959 | SeoJin Instech Level Transmitter SDG-3000 | |
| 1960 | SeoJin Instech Level Transmitter SLA | |
| 1961 | SeoJin Instech Level Transmitter SMS | |
| 1962 | SeoJin Instech Level Transmitter SCAP-IV | |
| 1963 | SeoJin Instech Level Transmitter SLT | |
| 1964 | SeoJin Instech Level Transmitter SDT-420 | |
| 1965 | SeoJin Instech Level Transmitter SGL | |
| 1966 | SeoJin Instech Level Transmitter ST-600 | |
| 1967 | SeoJin Instech Level Switch SDS-3000 | |
| 1968 | SeoJin Instech Level Switch SC5/SB3 | |
| 1969 | SeoJin Instech Level Switch SPS/SR7 | |
| 1970 | SeoJin Instech Level Switch SCAP | |
| 1971 | SeoJin Instech Level Switch SRF | |
| 1972 | SeoJin Instech Level Switch SVL | |
| 1973 | SeoJin Instech Level Switch SPT/SPL | |
| 1974 | SeoJin Instech Level Switch SFP | |
| 1975 | SeoJin Instech Level Switch SMC-7 | |
| 1976 | SeoJin Instech Level Switch SMC | |
| 1977 | SeoJin Instech Level Switch SHM-200 | |
| 1978 | SeoJin Instech Level Switch SHM-100 | |
| 1979 | SeoJin Instech Level Switch SFM | |
| 1980 | SeoJin Instech Level Switch SFS-2 | |