The Spectra Bladder Pump Sil 1.0, an award-winning, patented Groundwater Sampling Pump designed for VOC Sampling, Low Flow Sampling, Remediation, and more, is a top choice for professionals. With a maximum depth of 230ft, it's highly recommended for sampling purposes. Spectra Bladder Pump Sil 1.0 is the preferred option among 10 out of 10 consultants, making it the easiest to use Bladder Pump on the market. When paired with the Spectra Hydro Pro, it becomes the ultimate method for Groundwater Sampling. The 1.0 refers to its compatibility with 1-inch wells and larger.