Not exact matches
Sizes «small,» «medium,» and «large» tend to
vary with brand, so it's best to shop based on
exact measurements.
The
exact values we used for the fits
varied from balloon to balloon, but in all cases the balloon
measurements could be fit using just two (or sometimes three) phases.
The
exact meaning of surface
varies according to the
measurement method used, but it is between 1 millimetre (0.04 in) and 20 metres (70 ft) below the sea surface.»