spoke key wire gauge

What are the digits on the spoke key?

It seems 14 and 15 are those mostly used on the bikes
I see.

Here is what units(1) has in
/usr/share/units/definitions.units , but it seems none
of those match my spoke key. (?)

Some slots are very wide by the way - perhaps to be
used on MC spokes? Or on those bikes they have in
India to do transport...

# Wire Gauge
#
# This area is a nightmare with huge charts of wire gauge diameters
# that usually have no clear origin. There are at least 5 competing wire gauge
# systems to add to the confusion. The use of wire gauge is related to the
# manufacturing method: a metal rod is heated and drawn through a hole. The
# size change can't be too big. To get smaller wires, the process is repeated
# with a series of smaller holes. Generally larger gauges mean smaller wires.
# The gauges often have values such as "00" and "000" which are larger sizes
# than simply "0" gauge. In the tables that appear below, these gauges must be
# specified as negative numbers (e.g. "00" is -1, "000" is -2, etc).
# Alternatively, you can use the following units:
#

g00 (-1)
g000 (-2)
g0000 (-3)
g00000 (-4)
g000000 (-5)
g0000000 (-6)

# American Wire Gauge (AWG) or Brown & Sharpe Gauge appears to be the most
# important gauge. ASTM B-258 specifies that this gauge is based on geometric
# interpolation between gauge 0000, which is 0.46 inches exactly, and gauge 36
# which is 0.005 inches exactly. Therefore, the diameter in inches of a wire
# is given by the formula 1|200 92^((36-g)/39). Note that 92^(1/39) is close
# to 2^(1/6), so diameter is approximately halved for every 6 gauges. For the
# repeated zero values, use negative numbers in the formula. The same document
# also specifies rounding rules which seem to be ignored by makers of tables.
# Gauges up to 44 are to be specified with up to 4 significant figures, but no
# closer than 0.0001 inch. Gauges from 44 to 56 are to be rounded to the
# nearest 0.00001 inch.
#
# In addition to being used to measure wire thickness, this gauge is used to
# measure the thickness of sheets of aluminum, copper, and most metals other
# than steel, iron and zinc.

wiregauge(g) units=[1;m] range=(0,) \
1|200 92^((36+(-g))/39) in; 36+(-39)ln(200 wiregauge/in)/ln(92)
awg() wiregauge

# Next we have the SWG, the Imperial or British Standard Wire Gauge. This one
# is piecewise linear. It was used for aluminum sheets.

brwiregauge[in] \
-6 0.5 \
-5 0.464 \
-3 0.4 \
-2 0.372 \
3 0.252 \
6 0.192 \
10 0.128 \
14 0.08 \
19 0.04 \
23 0.024 \
26 0.018 \
28 0.0148 \
30 0.0124 \
39 0.0052 \
49 0.0012 \
50 0.001

# The following is from the Appendix to ASTM B 258
#
# For example, in U.S. gage, the standard for sheet metal is based on the
# weight of the metal, not on the thickness. 16-gage is listed as
# approximately .0625 inch thick and 40 ounces per square foot (the original
# standard was based on wrought iron at .2778 pounds per cubic inch; steel
# has almost entirely superseded wrought iron for sheet use, at .2833 pounds
# per cubic inch). Smaller numbers refer to greater thickness. There is no
# formula for converting gage to thickness or weight.
#
# It's rather unclear from the passage above whether the plate gauge values are
# therefore wrong if steel is being used. Reference [15] states that steel is
# in fact measured using this gauge (under the name Manufacturers' Standard
# Gauge) with a density of 501.84 lb/ft3 = 0.2904 lb/in3 used for steel.
# But this doesn't seem to be the correct density of steel (.2833 lb/in3 is
# closer).
#
# This gauge was established in 1893 for purposes of taxation.

# Old plate gauge for iron

plategauge[(oz/ft^2)/(480*lb/ft^3)] \
-5 300 \
1 180 \
14 50 \
16 40 \
17 36 \
20 24 \
26 12 \
31 7 \
36 4.5 \
38 4

# Manufacturers Standard Gage

stdgauge[(oz/ft^2)/(501.84*lb/ft^3)] \
-5 300 \
1 180 \
14 50 \
16 40 \
17 36 \
20 24 \
26 12 \
31 7 \
36 4.5 \
38 4

# A special gauge is used for zinc sheet metal. Notice that larger gauges
# indicate thicker sheets.

zincgauge[in] \
1 0.002 \
10 0.02 \
15 0.04 \
19 0.06 \
23 0.1 \
24 0.125 \
27 0.5 \
28 1

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