A straight valve with a nipple connector on one end and a 3/4-inch female thread on the other is a through-type control valve specifically designed for mismatched piping systems. One end features a "nipple" quick-connect interface (compatible with flexible tubing), while the other end has a 3/4-inch internal threaded connection (for mating with standard male-threaded pipes or equipment). Its primary function is to connect different-sized pipelines and control fluid flow, including on/off operation and flow regulation, offering convenient adaptation for low-pressure applications.