Lectron II Conductivity Gel. This gel is used with the carbon rubber electrodes and sticky fixers. Lectron II Conductivity Gel is a highly conductive, chloride free, hypo-allergenic electrode gel used in physical therapy for TENS and electrical muscle stimulation. It non-thinning formula will resist breakdown from body heat and salts in perspiration and will remain moist, thick and uniformly conductive throughout the most prolonged procedure or wearing period.