function wc_make_numeric_postcode( $postcode ) {
		$postcode           = str_replace( array( ' ', '-' ), '', $postcode );
		$postcode_length    = strlen( $postcode );
		$letters_to_numbers = array_merge( array( 0 ), range( 'A', 'Z' ) );
		$letters_to_numbers = array_flip( $letters_to_numbers );
		$numeric_postcode   = '';

		for ( $i = 0; $i < $postcode_length; $i ++ ) {
			if ( is_numeric( $postcode[ $i ] ) ) {
				$numeric_postcode .= str_pad( $postcode[ $i ], 2, '0', STR_PAD_LEFT );
			} elseif ( isset( $letters_to_numbers[ $postcode[ $i ] ] ) ) {
				$numeric_postcode .= str_pad( $letters_to_numbers[ $postcode[ $i ] ], 2, '0', STR_PAD_LEFT );
			} else {
				$numeric_postcode .= '00';
			}
		}

		return $numeric_postcode;
	}