usps priority mail flat rate shipping

usps priority mail flat rate shipping is a shipping service offered by USPS where the cost of shipping is determined by the size of the box or envelope, not the weight of the contents. Flat rate boxes and envelopes come in different sizes, and they allow customers to send items at a fixed price, no matter how heavy the contents are (within the weight limit). This is a popular option for businesses and individuals who want to send heavier items without worrying about fluctuating shipping costs. USPS Priority Mail Flat Rate also includes tracking and delivery in 1-3 business days.