Bottles are available in glass 40ml VOA vial size or plastic 125ml and 350ml sizes. The 40ml VOA vial can be used directly in standard laboratory autosampler equipment. With Snap Sampler VOA vials, the groundwater sample is never exposed to the open air from the point of collection downhole to the gas chromatograph. The 125ml or 350ml POLY bottle also seals in situ. The plastic bottle can be used for larger volume collection and for metals or other analytes where a plastic bottle is preferred. For non-volatiles, this bottle can be opened at the well head to combine in a larger bottle, transfer to a glass bottle (e.g. for SVOCs), or just to remove the internal spring before acidifying a metal sample. Snap Samplers with 40ml and 125ml bottles fit in 2-inch or larger monitoring wells. Snap Samplers with 350ml bottles fit in 4-inch or larger monitoring wells.