The 3-digit PIN is solely for the clients' guests. And this will therefore restrict the kind of controls they have with the photos they receive.

Keeping into account the client's privacy, once your client locks one or more albums for their guests using the Lock to Guest option, those albums will not be visible to the guests at all.

Similarly, if one or more photos have been hidden by your client, then even if the guests can access the album, they will not be able to view the pictures that the clients have hidden.

Once the guests access the albums, they have the freedom to view all the photos which are not hidden.

Further, if the client has enabled image download for the guests, then they will be able to download HQ images, too. Otherwise, they will be able to download web-optimised images by default.

Guests can also use the Play Slideshow button to view the images like a slideshow.