Do you need a certain lockbox to list on MLS?

[Roger Vi]

I am in Washington state (king county). If you sell your home "for sale by owner" and list it in the MLS, do you need to order a certain lockbox for keys? When I look at homes, sometimes I see the old keypad lock boxes, sometimes I see the digital ones where your agent can scan their key, and sometimes I see both. I just want to know if there is a rule for this. Also, if you do the old style lockbox is there a place on the listing where the agents can see the code/instructions to get in?