An inoculation loop, also known as a smear loop, inoculation rod or microstreaker, is a simple tool used primarily by microbiologists to take and transfer a small sample (inoculum) of a microorganism culture, for example for stripping on a culture plate. The tool consists of a thin handle with a loop about 5 mm wide or less at the end. It was originally made of twisted wire (such as platinum, tungsten or nichrome), but disposable moulded plastic versions are now common. The inoculation handle can be used for a variety of applications in microbiology: inoculation, serial dilution, sterile sampling, transfer and spreading of microbiological samples. Straight needles are best suited for taking single colony samples of microscopic organisms, while loop threads are capable of taking larger samples. The loops are smooth and flexible to facilitate the formation of uniform streaks without damaging the gel surface.