SPEC# (Specification Number) for Corrugated Packaging

What Is a Specification Number?

A specification number (SPEC#) is a unique item number assigned to a corrugated carton design that captures the complete set of specifications for that box. It serves as the definitive reference for every detail of the packaging — dimensions, board grade, flute type, ECT or Mullen rating, printing details, ink colors, die-cut pattern, and any special features or finishes. When you reference a SPEC# in a purchase order, the manufacturer knows exactly what to produce without ambiguity.

What Information Is Tied to a SPEC#?

The specification number links to a comprehensive spec sheet that documents every production parameter. This typically includes inside and outside dimensions (length, width, depth), board construction and grade, flute type, the BMC stamp values, print layout and colors, CAD die-line drawings, die identification, closure method, and any special treatments or coatings.

Having all of this information tied to a single reference number eliminates the need to re-specify your box every time you place an order. It also provides a clear audit trail for quality control, ensuring that every production run matches the approved design.

How SPEC# Simplifies Reordering

The greatest practical benefit of a specification number is reorder efficiency. Instead of describing your box requirements from scratch each time, you simply reference the SPEC# on your purchase order. The manufacturer pulls up the complete production record, including the stored die, printing plates, and quality parameters, and produces your boxes to the exact same standards as the previous run.

This system also reduces the risk of errors. Changes to a box design result in a new or revised SPEC#, creating a clear version history. Your procurement team and the manufacturer always know which version is current, preventing costly mix-ups during production.

SPEC# vs. SKU

While a SPEC# is a manufacturer’s internal design identifier, a SKU (Stock Keeping Unit) is typically the buyer’s inventory identifier. One box design (one SPEC#) may correspond to one or more SKUs in your inventory system, especially if the same box is used across different product lines or distribution channels. Both numbers are important, and your spec sheet should reference both for clear communication between your purchasing department and your manufacturer.

At President Container, we assign SPEC# numbers to every custom design we produce and maintain them in our production management system. Whether you are ordering corrugated shipping boxes, retail-ready packaging, or displays from Artisan Display, each design has a unique specification number for tracking and reordering.