A rebar (short for reinforcing bar), also known as reinforcing steel, is a common steel bar, and is commonly used as a tensioning device in reinforced concrete and reinforced masonry structures holding the concrete in compression. It is usually formed from carbon steel, and is given ridges for better mechanical anchoring into the concrete.

Metric bar designations represent the nominal bar diameter in millimetres. Bars in Europe will be specified to comply with the standard EN 10080 (awaiting introduction as of early 2007), although various national standards still remain in force (e.g. BS 4449 in the United Kingdom).

Model	Bar Size (mm)	Length	Grade	Specification	Surface	Type
Standard Deformed Bar	10, 12, 16, 20, 22, 25, 28, 32, 40	12 meter as Standard or Customize	250 , 460 and 500	MS146:2006 and BS4449:2005	-	-
Commercial Steel Bar	2.0 - 11.0	6 - 12meter	-	-	Round bar or Ribbed Bar	Low Carbon Steel