When should a unit be replaced

Features	___product_title___ ___product_old_price______product_price___ View
Availability	___product_availability___
Options	___product_options___
Author	___product_vendor___
Collection	___product_collection___
Rating	___product_rating___

Features	___product_label_sale___ ___product_label_new___ ___product_title___ ___product_old_price______product_price___ Availability ___product_availability___ View
Availability	___product_availability___
Options	___product_options___
Author	___product_vendor___
Collection	___product_collection___
Rating	___product_rating___