1, rarity: Altman Collection is produced in limited quantities, and each product is equipped with a unique number and certificate, which is even rarer. In contrast, Altman Bitter has no limited production and can be purchased in large quantities.

2. Price: Due to the rarity and importance of the Altman collection, the price is higher. In contrast, the price of special ultraman pen is relatively low.

3. Collection value: Altman's collection is equipped with a unique number and certificate, which has high collection value. However, the collection value of the special style of Altman pen is not as high as that of the collection style, and there is no unique number and certificate.