Bit flags PHP

<?php
$progress['1'] = "partial_easy";
$progress['2'] = "easy";
$progress['4'] = "partial_normal";
$progress['8'] = "normal";
$progress['16'] = "partial_heroic";
$progress['32'] = "heroic";
$progress['64'] = "partial_legendary";
$progress['128'] = "legendary";

$byte = '64'; // This would be from a database, stored in a TINYINT field (1 byte)

echo $progress[$byte];
?>