A linear transformation preserving volume

I recall you that a linear transformation $h$ preserves volumes if and only if $|\det h|=1$. So, the simplest example is $$h(x_1 , \dots, x_n)=(2x_1 , x_2 / 2 , x_3 , \dots , x_n)$$ represented by the diagonal matrix whose diagonal elements are $2, 1/2, 1, \dots , 1$.