Copper Multi-Hole (Kor-Less) Electrodes have a unique design which eliminates the standing spike, normally experienced with tubing type electrodes. Copper Multi-Hole (Kor-Less) Electrodes are especially useful in "blind" bottom type applications or "through hole" applications.99.9% Pure electrolytic Copper Multi-Hole (Kor-Less) tubes of diameter ranging from 0.50mm to 6mm in steps of 0.10mm, & length 400mm. TOLERANCE 0.D.; 0.015mm ELECTRO COPPER TUNGSTEN TUBULAR ELECTRODES :For EDM drilling of hard metals like carbides or heat treated metals. Diameters available 0.50mm to 6mm, in steps of 0.10mm and length 177.8 mm. Tolerance O.D. 0.015mm BRASS MULTI-HOLE (KOR-LESS) TUBULAR ELECTRODES:Brass Multi-hole (Kor-Less) Electrodes have a unique design which eliminates the standing spike, normally experienced with tubing type electrodes. Brass Multi-hole (Korn-Less) Electrodes are especially useful in "blind" bottom type applications or "through hole" applications.Brass Multi-Hole (Kor-Less) tubes of diameter ranging from 0.50mm to 6mm in steps of 0.10mm, & length 400mm. TOLERANCE 0.D.; 0.015mm