the bolt holes
51Underground mining (hard rock) — A three dimensional model of an underground mine with shaft access Underground hard rock mining refers to various underground mining techniques used to excavate hard minerals, mainly those containing metals[1] such as ore containing gold …
52Electric guitar — Fender Stratocaster String instrument Classification String instrument (plucked, either by fingerpicking, or with a pick.) …
53Wrench — For other uses, see Wrench (disambiguation). A set of chrome vanadium metric wrenches, open at one end, box/ring at the other. This type is commonly known as a combination wrench. A wrench or spanner is a tool used to provide grip and mechanical… …
54lock — lock1 lockless, adj. /lok/, n. 1. a device for securing a door, gate, lid, drawer, or the like in position when closed, consisting of a bolt or system of bolts propelled and withdrawn by a mechanism operated by a key, dial, etc. 2. a contrivance… …
55Sten submachine gun — Infobox Weapon name= Carbine, Machine, Sten caption= Sten Mk. II (trigger mechanism cover is missing) origin=flagcountry|United Kingdom type=Submachine gun is ranged=yes is UK=yes service=1941 ndash;1960s used by=See Users wars=World War II,… …
56Schmidt-Rubin — Infobox Weapon name= Schmidt Rubin rifles caption= Schmidt Rubin K31 Carbine origin=flagcountry|Switzerland type=Straight pull bolt action repeating rifle is ranged=yes service= 1869 – c. 1890 used by= Swiss Army wars= designer=Eduard Rubin and… …
57Gas-operated reloading — Gas operation is a system of operation used to provide energy to operate autoloading firearms. In gas operation, a portion of high pressure gas from the cartridge being fired is used to power a mechanism to extract the spent case and chamber a… …
58Punch (tool) — For punches used in punch presses, see Punching. A punch is a hard metal rod with a shaped tip at one end and a blunt butt end at the other, which is usually struck by a hammer. Punches are used to drive objects, such as nails, or to form an… …
59Crankset — A Shimano Deore right crankset, showing crank arm, spider, three chainrings and chainring guard …
60Seismic retrofit — Seismic retrofitting is the modification of existing structures to make them more resistant to seismic activity, ground motion, or soil failure due to earthquakes. Other retrofit techniques are applicable to areas subject to tropical cyclones,… …
