The A5253 header adapter is compliant with A5202/DT5202 and A5204/DT5204 boards. It mechanically adapts from the input edge card connector (type HSEC8‐170) to 65 3-pin connectors (AMPMODU type 3-102203-4). Each 3-pin connector mates to an AMPMODU type 102241-1. Of the headers mounted, 64 allows reading out and biasing as many SiPMs, while 1 allows reading out an external temperature sensor.