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מסכת כלים פרק יב משנה ב
קנה

The [wooden] beam
מאזנים של סרוקות

of a balance (this was a portable scale) of a comber (a craftsman who would comb wool or linen fibers)

טמא

is tamei (despite it being of wood)
מפני אונקליות

because of the hooks (metal hooks were hung from one end of this balance-beam and used to hold the merchandise being weighed; the metal component is what makes the wooden beam tamei);
ושל בעלי בתים

and [a balance] of householders,
אם יש בו אונקליות

if it has hooks
טמא

it is tamei. (the distinction from the comber's balance is that the householder's is the the former was always used with the hooks, while the latter would sometimes not have the hooks, and a string would be used to attach the item being weighed).
אנקלין של כתפים

The hooks of porters (a porter would carry packages suspended by hooks a pole that he carried on his shoulder, with one hook holding a package in front of him, and another behind him)
טהורה

are tahor (because in this case, the hooks are considered secondary to the main function of the wooden pole),
ושל רוכלים

and of peddlers
טמאה

are tamei (although similar in form to the porter's pole and hooks, the peddler's actually had receptacles at the end of the hooks).
רבי יהודה אומר

Rabbi Yehuda says
של רוכלים

[the hooks] of peddlers
שלפניו טמאה

that are in front of him (that is, the hook on the end of the pole that was in front of him) are tamei
ושלאחריו טהורה

and that are behind him are tahor (as this hook is not used to carry anything, but is rather used merely as a counterweight for the one in front).
אנקלי של דרגש

The hooks of a cot (this bed had legs and a frame, but instead of slats or a flat surface on which to rest or put a mattress, a leather sheet was attached to the frame with metal hooks)
טמאה

are tamei (they are deemed a part of the cot, and even though it was made of wood, the cot is susceptible to tumah as it was designed for one to rest their weight upon it);
ושל נקליטין

and [the hooks] of bed poles (these extended upward at the foot and head of the bed, and were used to drape a canopy over the bed)
טהורה

are tahor;
של שדה טמאה of a chest are tamei (this refers to hooks attached to a small box to hand it from the wall; as it had a receptacle, the box was susceptible to tumah);
ושל אקון טהורה and of a cauf is tahor (this was a reed or wooden cage used by fishermen to trap fish and hold them in the water while still alive, it was attached by the hook to a rope or chain, and lowered into the water; it is tahor because it lacked a receptacle and/or did not have the form of a vessel);
של שולחן טמאה

[the hook] of a table is tamei (the hook was used to hang the table out of the way when not in use; it is tamei as the table is tamei, the table is tamei for being a utensil that directly serves people);
של מנורת העץ [the hook] of a wooden candelabra (which lacked a receptacle, rather cups containing oil and wicks were placed upon it)
טהורה is tahor;
זה הכלל this is the rule:
המחבר לטמא טמא that which is attached to something tamei is tamei;
והמחבר לטהור טהור and that which is attached to something tahor is tahor; (as they do not have names of their own, but rather are components of other utensils)
וכולן and all of these [hooks]
אחת אחת בפני עצמן each one on its own
טהורות is tahor.
 

פרק יב משנה ג
כסוי טני של מתכת The metal cover of a teni (a type of metal box which is susceptible to tumah),
של בעלי בתים of householders
רבן גמליאל מטמא Rabban Gamliel ruled are tamei (as it could be turned upside down and used as a utensil in its own right)
וחכמים מטהרין and the Sages rules are tahor (as it does not have its own name, and so the fact that it has a receptacle is of no matter as it is meant to be used as a cover),
ושל רופאים טמא and of doctors is tamei (as doctors would use the cover to hold medicines).
הדלת שבמגדל The [metal] door of a [wooden] cabinet (that is not susceptible to tumah)
של בעלי בתים of a householder
טהורה is tahor
ושל רופאים טמאה and of a doctor is tamei (as the doctor hangs his tools from the door, making it a utensil in its own right, and not merely a part of the cabinet).
היתוכין טמאים Tongs are tamei
והפרכין טהורין and perachin (these were tongs attached to an oven and used to move vessels inside of it) are tahor.
 עקרב בית הבד The akrav of an olive press (this was a bent piece of metal attached to a wooden beam of the press used to crush the olives before they were pressed under a heavier beam) 
טמאה is tamei (as this metal part does the crushing, not the wooden beam)
ואנקלי שבכתלים and a hook in the wall (used to hang utensils)
טהורה is tahor. (as they are attached to the wall, and by extension the ground).