staple

General is iron wire, or nickel plating nickel above of zinc alloy as antirust, wire inside
Have Fe C S P Mn Si, and a small number of Cu etc, including the content of Fe in 99% around. Staples have two kinds, one kind is made of iron, still have a kind of were of brass.

Nail book needle size: 10 #, unified (24/6), 26/6, thick layer ShuDing: 23/8, 23/10, 23/13, 23/15, 23/17, 23/19, 23/23, American book needle B8, B88.
Book needle specification: 10 # book machine two needles wide for 8.4 mm, high for 5mm. Other ShuDing two needle wide 11.5 mm, high depends on the size of the ShuDing denominator.