Gentleheel® Neonatal Lancet Fullterm Sterile lancet is a safe, and very effective method of obtaining blood samples from the heels of infants. A surgical stainless steel blade incises to a controlled standardized depth and length above the pain fibers making the procedure virtually pain-free. Gentleheel® lancets create incisions that allow blood to flow more freely, reducing the need to squeeze the foot. Blade permanently and automatically retracts after use. 1mm incision depth; 2.5mm length. Single use.