  The Extreme ultraviolet Imaging Spectrometer (EIS) on board the Hinode
spacecraft has been operating since 2006, returning high resolution data in the
170-212 and 246-292 A wavelength regions. EIS has four slit options, with the
narrow 1" and 2" slits used for spectroscopy and the wide 40" and 266" slits
used for monochromatic imaging. In this article several properties of the 40"
slit (or slot) are measured using the Fe XII 195.12 A line, which is formed at
1.5 MK. The projected width of the slot on the detector shows a small variation
along the slit with an average value of 40.949". The slot image is tilted on
the detector and a quadratic formula is provided to describe the tilt. The tilt
corresponds to four pixels on the detector and the slot centroid is offset
mostly to the right (longer wavelengths) of the 1" slit by up to four pixels.
Measurement of the intensity decrease at the edge of the slot leads to an
estimate of the spatial resolution of the images in the x-direction. The
resolution varies quadratically along the slot, with a minimum value of 2.9"
close to the detector center. Intensities measured from the slot images are
found to be on average 14% higher than those measured from the 1" slit at the
same spatial location. Background subtraction is necessary to derive accurate
intensities in quiet Sun and coronal hole regions. Prescriptions for deriving
accurate slot intensities for different types of slot datasets are presented.
