Hang the Projector on the Ceiling
1Loosely install the 12 mm knurled knobs, flat washers, and conical spacers to the 2 hinge pins on the base box (Figure 4).
knurled knob
spacer washer 
knurled knob
slide projector
bracket here between
the base box and the knurled knob
FIGURE 4
Attach knurled knobs to the side of the base box
2Make sure your cables are pulled through the center hole of the base box, then carefully lift the projector and turn it upside down so the mounting plate faces the ceiling.
3Insert the projector and mounting bracket into the base box through the space between the knurled knobs and base box (Figure 4). Slide the projector bracket forward until the knurled knobs rest fully in the vertical slots and support the projector. Tighten the knurled knobs completely.
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