OEM vs aftermarket

VacPartFit labels fit, not brand loyalty. The difference still matters at checkout.

OEM

The part the manufacturer sells under its own item number — iRobot 4639161, Dreame X50 kit, Shark XPRFRV2500. Confirmed rows start here.

Aftermarket

A third-party filter or bag that claims the same hole pattern. It can work. It is still Unverified on this site until the manufacturer names that SKU, which they almost never do.

How to read a listing

• If the listing reprints the official item number and the official model list, treat it as a reseller of the OEM SKU.
• If the listing says “compatible with 40 models” and no official URL, stop. That is marketing, not a source.
• Batteries and sealed packs follow the brand manual even when a third-party pack is cheap.

Retailer links on Confirmed pages come after the verdict. They are not the verdict.