The AdirPro Mini Stakeout Prism Pole is ideal for high accuracy stakeout, being small and compact makes it great for eccentric trivial locations. Its lightweight which makes it easy to hold in place and manufactured with a built-in 40-minute bubble vial providing accuracy for extended time. The pole is constructed of sturdy aluminum and coated with electrostatic powder paint. Its easy to set up, convenient to store and transport, measures just 1.28 ft. (0.39 m), built with a 5/8 in. male stud, a removable stainless steel sharp point, includes a heavy-duty bag along with carrying straps. A 40-minute. vial is a less sensitive leveler than the 20-minute. or 8-minute. it would be best for projects that involve holding the pole by hand thereby providing accuracy for extended time, whereas the other vials though they are more accurate wont be able to provide the best in areas with lots of vibrations such as near roads or at construction sites, therefore in those areas it would be best to use a 40-minute. vial.