Systems and methods for a positron emission tomography (PET) kit are described. A PET detector kit may include a gantry, a plurality of PET detector modules, and an event processing device. A PET detector module may include a housing, a crystal, a light detector, and a communication component. The housing may include at least one connective element configured to removably and adjustably couple the PET detector module to the gantry. The crystal may be located within the housing. The light detector may be configured to detect light emitted by the crystal. The communication component may be configured to communicate data from the at least one light detector to an event processing device. The event processing device may receive data from the plurality of PET detector modules and may cause the one or more processors to determine coincidence events based on the received data.
