The M-9 Male UCA is intended for intermittent use,
functions with a medical aspirator, and the suction is nine (9)
inches of mercury — adjust M-9 aspirator pressure to 230 mm Hg.
The M-15 version is for continuous critical use (i.e. prostate
enlargement) and is fifteen (15) inches of mercury. The F-15
Female UCA functions with a medical aspirator and the suction is
fifteen (15) inches of mercury — adjust F-15 aspirator pressure
to 390 mm Hg.