Canon EOS-1 - Manual (Page 23)

Power Drive Booster El________________
The film transport system presents
two configurations. The camera is
lightweight and compact when the
Power Drive Booster El is not
attached, and the built-in motor
drive advances the film at a rate of
2.5 frames per second. If you need
more speed, attaching the Power
Drive Booster El raises the film
advance speed to 5.5 fps, enabling
very rapid-fire continuous shooting.
In addition, the rugged, sure-grip
power drive booster has a shutter
button and AE lock button posi­
tioned on the base so that operating
the camera vertically feels the same
as when holding it horizontally. The
motordrive batteries power the
camera when attached. “AA” alka­
line or Ni-Cd batteries can be used.
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