1.high quality nails
2.nails have different shapes
3.material:iron or steel
4.usd in constructions
5.it is very concrete.

1.high quality common iron nails

2.nails have different shapes
3.material:iron or steel
4.usd in constructions
5.the nail quality is very good
6.it is very concrete.

7.In engineering, carpentry and construction, the nails that are pointed like the hard metal (usually steel), wood and other materials used as stationary. nails have different shapes, the most common nail is known as "iron nail"