Wallach Needle Electrodes 0.8mm dia. x 25.4mm NEEDLE (909005). Wallach high quality stainless steel disposable needle electrodes come in a single sterile package with five packages to a box. Needle electrodes are interchangeable with any electrosurgical unit. 3/32" diameter shaft. Made in the U.S.A. 5/BX. Priced per box. FREE Shipping!