There are some appearance packs that do not have their individual items shown in the Marketplace, so players cannot check what it would look like before acquiring the pack.
Below you can find the ones that cannot be checked in the preview and their name above the image. This way, you can get an idea:
Bound Sylvas Nocturne Crate
Wrapped Blue Devils Gear
Wrapped Flamewolves Gear
Wrapped Flashy Steamracer Leathers
Wrapped Mirrorshine Steamracer Leathers
Wrapped Skydark Steamracer Leathers