The HJ-4A magnetic stirrer is easy to operate and has stepless speed regulation. It can precisely and stably stir the liquid solution in a wide speed range, and is especially suitable for the test of small volume samples. Magnetic stirrers can be divided into three types: non-heating type, heating type, and constant temperature type. Some models have added two-way and multi-head stirring functions. It is a desirable tool for modern petroleum, chemical industry, medicine and health, environmental protection, biochemistry, experimental analysis, education and scientific research.

| model | HJ-2A | HJ-4A | HJ-6A |
| Maximum stirring volume | 1000ml*2 | 1000ml*4 | 1000ml*6 |
| stirring speed | 2400rpm | 2400rpm | 2400rpm |
| heating power | 200w*2 | 200w*4 | 200w*6 |
| Temperature control range | RT+~100℃ | RT+~100℃ | RT+~100℃ |
| Working disc size | Φ125mm*2 | Φ125mm*4 | Φ125mm*6 |
| Dimensions | 280*280*120mm | 560*280*120mm | 850*280*120mm |
| Way of working | Digital temperature control | Digital temperature control | Digital temperature control |