The dual-device DC fixtures work with systems that provide DC and thermal stimulus only to the device. There are no RF signals available. This option provides the most channel density of any fixture. As with the RF-Ready DC fixture, it does not contain an on-board heater, but shares a common heater block with neighboring channel. The device mounts in a PGA-style package and does not provide room for external bias or stabilization components. Therefore, it is important to know that the devices are inherently stable without those elements near the device.