$re = '/([\d.]+) oz/m';
$str = '0 Adult Dog Food 18-Count, 3.5 oz Pouches 3.5
1 Gardetto’s Snack Mix, 1.75 Ounce 1.75
2 Colgate Whitening Toothpaste, 3 oz Tube 3
3 Adult Dog Food, 13.2 oz. Cans 24 Pack 13.2
4 Keratin Hair Spray 2!6 oz 6';
preg_match_all($re, $str, $matches, PREG_SET_ORDER, 0);
// Print the entire match result
var_dump($matches);
Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for PHP, please visit: http://php.net/manual/en/ref.pcre.php