針金 is read as はりがね (harigane) and means wire.
はりがね
harigane
はりがねざいくひょうげん
wire frame representation
はりがねざいく
wirework
はりがねむし
wireworm (click beetle larva)
はりがねせいぞうこうじょう
wireworks
はりがねせいぞう
wiremaking
きんしん
gold needle (esp. an acupuncture needle)
きんばり
gold hook (esp. for fishing)
はり
counter for stitches
しんろ
course
はりせんぼん
porcupinefish (Diodon holacanthus)
はりこ
seamstress
はりめ
seam