Abstract: A yarn splicer having a closable pneumatic chamber which is permanently open at each end so as to receive the yarns to be spliced from opposite ends, discrete yarn rolling means arranged on either side of the splicer adjacent each end of the chamber to engage the running portion of a respective yarn in the chamber, and yarn gripping means also disposed at either end of the chamber to engage the respective loose ends of the yarns. Actuation of the splicer results in a prescribed rolling action on the yarns in a direction to completely detwist them, and deactivation results in an equal and opposite action on the yarns so as to restore the original twist.The preferred arrangement has a biased lost motion linkage between the actuation means and the chamber-mechanism which provides a drive to the rolling means and gives an over-twist to the yarns during detwisting and which recovers the over-twist as well as restoring the original twist at the termination of the splice.