Amazon defines oversized as any item where the longest side exceeds 18 inches, or the unit weight exceeds 20 lbs. Oversized items have higher FBA fees and different carton and pallet requirements.
For prep, oversized items often need extra bubble wrap or foam protection, custom carton builds, Team Lift labels on boxes over 50 lbs, and pallet staging for items that cannot be processed as individual cartons.
Not every prep center can handle oversized efficiently. Ask about receiving dock height, pallet jack availability, and whether they have experience with the specific product category.
Oversized prep costs more per unit because the handling time is higher. Make sure your quote reflects the actual size and weight of the product, not standard small-parcel unit pricing.