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<h2 id="table">Table</h2> <table><tbody><tr><th colspan="3">Diameter</th><th>Thread density</th><th rowspan="2">As <a href="/facts/British_Standard_Cycle/996PwSkv">BSC</a>?</th><th colspan="2">Nut, approximate</th><th rowspan="2">Tap drill</th></tr><tr><th colspan="2">(in)</th><th>(mm)</th><th>(in−1)</th><th>(mm)</th><th>(in)</th></tr><tr><td>3⁄16</td><td>0.19</td><td>4.83</td><td>32</td><td>Yes</td><td>8.59</td><td>11⁄32 6pt</td><td>5⁄32 in</td></tr><tr><td>7⁄32</td><td>0.22</td><td>5.59</td><td>28</td><td>No</td><td colspan="2"></td><td><i>4.6 mm</i></td></tr><tr><td>1⁄4</td><td>0.25</td><td>6.35</td><td>26</td><td>Yes</td><td>11.30</td><td></td><td><i>5.3 mm</i></td></tr><tr><td>5⁄16</td><td>0.31</td><td>7.87</td><td>22</td><td rowspan="13">No</td><td>13.35</td><td>17⁄32</td><td>17⁄64 in</td></tr><tr><td>3⁄8</td><td>0.375</td><td>9.53</td><td>20</td><td>15.24</td><td>5⁄8</td><td><i>8.2 mm</i></td></tr><tr><td>7⁄16</td><td>0.44</td><td>11.18</td><td>18</td><td>18.03</td><td>11⁄16</td><td><i>9.7 mm</i></td></tr><tr><td>1⁄2</td><td>0.50</td><td>12.70</td><td>16</td><td>20.83</td><td>13⁄16</td><td>7⁄16 in</td></tr><tr><td>9⁄16</td><td>0.56</td><td>14.22</td><td>16</td><td>23.37</td><td>15⁄16</td><td>1⁄2 in</td></tr><tr><td>5⁄8</td><td>0.63</td><td>16.00</td><td>14</td><td>25.65</td><td>1 6pt</td><td>14 mm</td></tr><tr><td>11⁄16</td><td>0.69</td><td>17.53</td><td>14</td><td>27.94</td><td>1+1⁄8 6pt</td><td>15.5 mm</td></tr><tr><td>3⁄4</td><td>0.75</td><td>19.05</td><td>12</td><td>30.48</td><td>1+1⁄4 6pt</td><td><i>16.75 mm</i></td></tr><tr><td>7⁄8</td><td>0.88</td><td>22.35</td><td>11</td><td>33.02</td><td>1+5⁄16</td><td>25⁄32 in</td></tr><tr><td>1</td><td>1.00</td><td>25.40</td><td>10</td><td>37.59</td><td>1+1⁄2</td><td><i>22.75 mm</i></td></tr><tr><td>1+1⁄8</td><td>18</td><td>457.20</td><td>9</td><td>42.42</td><td>1+11⁄16</td><td>26.50 mm</td></tr><tr><td>1+1⁄4</td><td>1.25</td><td>31.75</td><td>9</td><td>47.24</td><td>1+7⁄8</td><td>28.75 mm</td></tr><tr><td>1+1⁄2</td><td>1.50</td><td>38.10</td><td>8</td><td>56.39</td><td>2+1⁄4</td><td>34.50 mm</td></tr></tbody></table> <h2 id="bibliography">Bibliography</h2> <ul><li>P.A. Sidders, ed. (1969). <i>Guide to World Screw Threads</i>. New York: Industrial Press. <a href="/facts/ISBN_(identifier)/15AdSPa9">ISBN</a> 0-8311-1092-9.</li></ul> <h2 id="external-links">External links</h2> <ul><li><a href="https://web.archive.org/web/20180828071712/http://www.britishfasteners.com/threads/bsf.html">Thread sizes</a> at the <a href="/facts/Wayback_Machine/nmQ3a6JC">Wayback Machine</a> (archived 2018-08-28)</li> <li><a href="http://www.sat.dundee.ac.uk/~psc/spanner_jaw.html">Jaw sizes for sockets and spanners/wrenches</a></li> <li><a href="http://www.dropbears.com/u/utilities/spanners.htm#">Spanner size chart</a></li></ul> <h2 id="references">References</h2> <ol> <li id="fn:1"><p>Glanfield, John (2001). The Devil's Chariots. Sutton. p. 87. ISBN 0-7509-4152-9. <a href="0-7509-4152-9" target="_blank">0-7509-4152-9</a> <a href="#fnref:1" class="footnote-back-ref">↩</a></p></li> <li id="fn:2"><p>Sidders 1969, p.16 <a href="#fnref:2" class="footnote-back-ref">↩</a></p></li> </ol>