Electrologists can’t see what is happening under the skin in the follicle, so have to use their sense of touch and make note of any visual indicators above the skin to gauge if an insertion is correct or whether they need to withdraw the needle and insert again. electrologists work blind and need ‘follicle feedback’ to guide them correctly to the target area. Although experienced electrologists can work with either, there is more feedback with two piece needles. These needles are disposable & coated with a specialist medical grade insulation material.