Depending on what you are sending, a "piece" for Next Day Air can be:

: Used for urgent documents and single-piece shipments that do not have a specific weight.

: Each "piece" or package can weigh up to 150 lbs .

: If a Next Day Air piece is delivered late, you may be eligible for a refund through the UPS Service Guarantee . Package Type Codes - UPS

: Any standard shipping box that meets UPS size and weight requirements (up to 150 lbs). Shipping Guidelines for Next Day Air

: Maximum length of 108 inches and a combined length plus girth of 165 inches .