These sterile Trace DNA Swabs are prefilled with 91% isopropyl alcohol which will self saturate the foam collection tip. The alcohol saturated tip may be used to collect multiple types of biological DNA samples from visible stain evidence and potential invisible trace samples. The alcohol will preserve the collected DNA sample and does not require drying. Package swabs in plastic evidence vials. Provided in packages of 40 or 400 trace DNA swabs.