Glassware Glossary
FITTER (F)
Fitter size is the diameter
of the glass where the glass
attaches to the fixture or lamp.
HEIGHT (H)
Distance between the two
farthest points opposite
each other on the top and
bottom of the glass that
form a vertical line.
DIAMETER (D)
Distance between two
opposite points at the
widest part of the glass
that form a horizontal line.
NECKLESS
A piece of glass without a neck.
CENTER HOLE
The opening on a neckless
shade and measured like a
fitter. If a piece of glass has
a fitter and a center hole, the
center hole is used for lock-up.
DEPTH
Distance from the center
point inside the glass to the
point directly opposite, this is
measured without mounting.
BULGE
The diameter measured at the
widest part of a chimney.
TOP OPENING
Distance between the two
farthest points opposite each
other on the top of a student
shade. All top openings are
wide enough and made to fit
over the average chimney.
THREADED NECK
A fitter that attaches to the
fixture or lamp by means
of threads in the glass.
NOTCHED FITTER
Designed to lock tightly into
specially designed holders
with ¼ turn.
This wattage guide is a
general recommendation
only. Actual wattage ratings
are influenced by fixture
type, bulb location and ambi-
ent temperature. The light
source should be located at
the center of each shade.
Feature
Polyethylene
Acrylic Polycarbonate
Heat Resistance
G
G
E
Quality of Seams
F
E
E
UV Resistance
F
E
F
Strength
G
G
E
Light Transmission
F
E
G
Wall Thickness Uniformity
G
G
E
Shatter Resistance
E
F
G
Surface Characteristics
G
E
G
Appearance vs. Time
G
E
G
Strength vs. Time
G
E
F
Overall Appearance
G
E
G
Polyethylene
Globe
Watts
6"
40
8"
75
10"
100
12"
150
14"
200
16"
200
18"
250
—
—
—
—
Acrylic
Globe
Watts
6"
60
8"
75
10"
100
12"
150
14"
150
16"
200
18"
200
Cylinder
Watts
5"
60
Polycarbonate
Globe
Watts
6"
75
Cylinder
Watts
5½"
60
5¾"
60
6¼"
60
7¼"
60
8½"
60
8¾"
60
—
—
Feature Comparison Chart
Recommended Maximum Incandescent Wattage Ratings
KEY:
E = Excellent
G = Good
F = Fair
Plastic Material Guide
GLASSWARE
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