What is the right hook to use in WooCommerce for handling the post of the sale price?

For a plugin for WooCommerce I need to find the hook which can be used to handle some additional actions when the sale price of a product is added or changed. When I experiment with ‘transition_post_status’ somehow the initial sale price seems to be invisible, so I can’t detect the change.

You can use “save_post” hook to detect whether the sales price is modified or added.

Thanks,