TSZ - 4A type strain control triaxial apparatus used to measure in three equal strain soils, add lotus under the way of shear strength, instrument can undertake UU, CU, CD test could also to four soil samples in different around pressure consolidation experiments. This product has the shear high efficiency (especially in the consolidated undrained shearing tests conducted in 24 hours, can finish a sample of shear strength determined). Instrument performance stability, simple operation, and suitable for geotechnical tests production-oriented units using.