WHCD ultra-thin hollow hydraulic wrench adopts high-strength light metal to the greatest extent, and the power head is integrally formed to comprehensively improve the strength and service life; Large torque / weight ratio, double acting, high speed, large angle and high efficiency. One power head can be used with a variety of working heads, with a wide working range of  360 ° × 360 ° rotating hose joint makes it easy to use in a narrow space without mechanism jamming. The torque repetition accuracy is up to ± 3%. No other tools are required when loosening.     The storage box protects the wrench head from damage, immersion and dirt. There are few moving parts, durable and convenient maintenance.