Act with due care, and check before you pass it on Art. 20(1), Art. 20(2)
When making a product available on the market, a distributor must act with due care in relation to the requirements of the CRA (Art. 20(1)). Before making it available, you must verify the product bears the CE marking, and that the manufacturer and importer have complied with their identification, contact, instructions, support-period, and declaration duties and provided you the necessary documents (Art. 20(2)).
This is a lighter, verification-level duty than the manufacturer's: you are not assessing conformity yourself, you are checking the visible signs that others did their job before the product reaches you.
Hold back non-conforming products Art. 20(3), Art. 20(4)
Where you consider or have reason to believe, on the basis of information in your possession, that a product or the manufacturer's processes are not in conformity, you must not make it available until it is brought into conformity; where it poses a significant cybersecurity risk you must, without undue delay, inform the manufacturer and the market surveillance authorities (Art. 20(3)).
If a product you have already made available turns out to be non-conforming, you must make sure the necessary corrective measures are taken, or that it is withdrawn or recalled as appropriate (Art. 20(4)).
Vulnerability, cooperation, and cessation duties Art. 20(4), Art. 20(5), Art. 20(6)
On becoming aware of a vulnerability in the product, you must inform the manufacturer without undue delay; where the product presents a significant cybersecurity risk, you must immediately inform the market surveillance authorities of the Member States where you made it available (Art. 20(4)). On a reasoned request, you must provide the information and documentation needed to demonstrate conformity, and cooperate with the authority (Art. 20(5)).
If you become aware that the manufacturer has ceased operations and can no longer comply, you must inform the relevant market surveillance authorities without undue delay and, so far as possible, the users of the products already placed on the market (Art. 20(6)).
The own-brand and substantial-modification trap Art. 21
The distributor role ends the moment you change your relationship to the product. Placing it on the market under your own name or trademark, or carrying out a substantial modification, makes you a manufacturer for the purposes of the CRA, subject to Articles 13 and 14 in full (Art. 21). Reselling or distributing a product unchanged, under the original brand, keeps you in the lighter distributor role.