How to Add SKU to checkout/order-received page woocommerce

Use this code to add woocommerce SKU (Stock Keeping Unit) value to checkout and order-received pages.
add this to your theme functions.php

/**
 * Adds product SKU to the WooCommerce order details page
 * Uses WooCommerce 2.5 or newer
 */
add_action( 'woocommerce_add_order_item_meta', 'jk_add_item_sku', 10, 3 );
function jk_add_item_sku( $item_id, $values, $cart_item_key ) {

  $item_sku = get_post_meta( $values[ 'product_id' ], '_sku', true );

  wc_add_order_item_meta( $item_id, 'sku', $item_sku , false );

}