Product Key Features Field

product_key_features.php

<?php
// Display Input Field on Backend
add_action( 'woocommerce_product_options_general_product_data', function () {
  global $woocommerce, $post;  
  echo '<div class="options_group">';  
woocommerce_wp_text_input( 
	array( 
		'id'          => 'product_key_features', 
		'label'       => __( 'Product Key Features', 'woocommerce' ), 
		'placeholder' => 'Enter product key features (3 words)',
		'desc_tip'    => 'true',
		'description' => __( 'The product key features, keep it simple', 'woocommerce' ) 
	)
);  
  echo '</div>';	
}
);


// Save Input Field on Backend
add_action( 'woocommerce_process_product_meta', function ( $post_id ){	
	$woocommerce_text_field = $_POST['product_key_features'];
	if( !empty( $woocommerce_text_field ) )
		update_post_meta( $post_id, 'product_key_features', esc_attr( $woocommerce_text_field ) );
}
);


// Display Input Field on Frontend
add_action('woocommerce_after_shop_loop_item_title', function (){
  $value = get_post_meta( get_the_ID(), 'product_key_features', true);
  if(strlen($value) != null && strlen($value) > 0) {
	echo '<p class="blc_description">'.get_post_meta( get_the_ID(), 'product_key_features', true ).'</p>';
  }
}, 22 );