my @sku   =  qw/SKU1 SKU2 SKU3/;
my @tslh  =  qw/t s l h/;
my @colors = qw/BLU GRN WHT BLK /;  
my @sizes = qw / S M L XL 2X /;

print map { $col = $_; map { $siz = $_; map {$a1 =$_; map "$_ $a1 $siz $col\n", @sku;} @tslh} @sizes } @colors;