http://ngccoin.com/services/multi-coin.asp

"The NGC Multi-Coin Holder can accommodate from two to five coins, and up to six coins for Proof and Mint Sets. Each coin is given its own certification number on the large format label. Coins in the Multi-Coin Holder are therefore eligible for inclusion in the NGC Registry individually.

Utilizing the same state-of-the-art plastics as the NGC’s single-coin holders, Multi-Coin holders are sonically sealed, tamper-evident, and include a security hologram."