Cult of the Dragon Masks very in design wildly from group to group depending on who is overseeing their production, the dragon or dragons that the members worship and several other factors.

The thing that all CotD Masks have in common is the procedure of making the masks and what they allow the wearer of the mask to do, along with all the benefits their master receives for each mask that is created. The Masks are made from shed or lost dragon scales. Larger scales can often result in multiple masks being made. The process of making the masks in a secret ritual that the Cult of the Dragon guards and only allows its most tested and devout members to learn. It assumed by scholars that some variation of the Fabricate spell is used in conjunction with a secret ritual.

Attunement: Only someone who truly worships the dragon whose scales the mask was made from can attune to the mask. 

Once attuned, the wearer of the Cult of the Dragon Mask is granted the following abilities:

• Find Your Master. You always know which way to travel to get to your master (The dragon who's scales were made to forge the mask). You have no idea the distance, only the direction you need to travel to get to them.
• Telepathy. You can speak telepathically to your master as long as you are on the same plane of existence with them.
• Remote Viewing. Your master can focus on you and see, hear and smell everything just as if they were there as long as you are on the same plane of existence with them. During this time you can not see, hear or smell anything even though you are still conscious. 
• Mind control. Your master can take over your body as long as you are on the same plane of existence with them, in addition to the remote viewing ability, your master gains complete control of your body, abilities, and powers. During this time, your mind is unconscious and is completely unaware of what is happening. 
• Blessing of the Master.  If you are within 100 feet of your master, you gain the effects of a Bless spell.
• Resistance. You gain resistance to the type or types of damage of your master's breath weapon(s). This effect does not work versus your master.
• Mind Shielding. You are immune to magic that allows other creatures to read your thoughts, determine whether you are lying, know your alignment, or know your creature type. Furthermore, this effect allows someone to lie in a Zone of Truth without the caster of the spell knowing its a lie. This effect does not work versus your master.
• Report Death. If you die while wearing the Cult of the Dragon Mask, your master is made aware of your death as long as you are on the same plane of existence with them.

Additional Lore. Due to the amount of information the dragon receives from his followers, dragons worshiped by the Cult of the Dragon have been known to go out of their way to pull from their own body larger scales that can be used to form dozens of masks. If the dragon is still alive he regenerates the lost scale in several days, if the dragon is already a dracolich they don't even care about the loss of scales anymore.