The combo is available with 3 switching contacts (NCJ9FI-*). These contacts are closed to the TIP / RING / SLEEVE of the ¼" jack, when no plug is mated. The circuit opens when connecting a ¼" plug into the Combo. We also offer an additional switching ground contact (NCJ10FI-*), which is closed to the XLR chassis ground and opens when connecting a XLR cable connector.