Nails are made of iron. If you are as tough as iron then you are really tough.
This is a simile comparing someone or something to nails. Nails are hard and tough, so this person or thing is being declared to be very hard and tough.
Think about this and you can figure it out. Are nails hard and tough? The kind made of steel certainly are - this simile compares someone's strength and toughness to that of a nail.
Tough as Nails - 2010 was released on: USA: 18 March 2010
The cast of Tough as Nails - 2010 includes: Stumpo Cindy Stumpo Joe Rebholz Michael Stumpo Samantha
Tough as Nails - 2010 2010-04-13 was released on: USA: 13 April 2010
Tough as Nails - 2010 2010-04-21 was released on: USA: 21 April 2010
Keratin
Tough as Nails - 2010 Cindy Inspects the Unexpected 1-8 was released on: USA: 12 May 2010
Tough as Nails - 2010 Cindy Takes on Miami 1-6 was released on: USA: 15 April 2010
Tough as Nails - 2010 Cindy's Fresh Start 1-5 was released on: USA: 8 April 2010
Tough as Nails - 2010 It's Marble Madness 1-9 was released on: USA: 19 May 2010
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