TDMA based MAC protocols can provide a very good utilization of the shared radio resources, especially at high input loads, in synchronized mobile ad hoc networks (MANETs). Global positioning systems like GPS or GALLILEO should provide a very good timing accuracy for synchronization of nodes. This paper presents a medium access protocol for mobile ad hoc networks, called CROMA (Collision-free Receiver-Oriented MAC). It operates in a slotted environment, in a dynamic and distributed way. In this protocol, receivers act as local base stations on a given slot. This paper gives a particular focus on the multislot communications feature of the protocol, which is described in details and analyzed through simulations in a challenging multihop situation. Moreover, an analytical study of CROMA in a fully-connected network is provided.