What is the names of the sacraments at the service of communion?

The sacraments at the Service of Communion is from the Catechism, the header for Chapter Three of Part Two: Question 1533 names Baptism, Confirmation, and Eucharist as the Sacraments of Initiation. In 1544 It mentions two other sacraments, Holy Orders and Matrimony directed towards the salvation of others. These five sacraments are "at the Service of Communion".