The Delmhorst 608/4 Replacement Moisture Insulated Pins, 4" length with 3-1/4" penetration, Pack of 4 is used on roofing, insulation, timber, poles, and EIFS. The pins measure 4" overall, and penetrate 3 1/4". Standard on 21-E and 18-ES electrodes, Also available in 7” length with 6” penetration as 608/001.
