The ASRock RX 6600 XT Phantom Gaming D uses a mostly black design with red highlights. On the back, you'll find a high-quality metal backplate with cutouts to let some airflow through.
Dimensions of the card are 30.0 x 13.0 cm, and it weighs 899 g.
Installation requires three slots in your system. The card is only slightly thicker than the PCIe slot cover, but that still makes it a triple-slot card. That said, it should fit just fine if you have a very small card next to it, like a tiny sound card.
Display connectivity includes three standard DisplayPort 1.4 and one HDMI 2.1. Display and media capabilities are identical to the rest of the RDNA2 family.
The card has one 8-pin power input. This configuration is rated for up to 225 W of power draw.
The AMD Radeon RX 6600 series doesn't support multi-GPU.
The heatsink provides cooling not only for the GPU, but the VRM circuitry and memory chips, too. The thermal pads for the memory are 1.0 mm thick, and those on the VRM are 1.5 mm thick.
The backplate is made out of metal and protects the card against damage during installation and handling. The thermal pads on the backplate are 2.5 mm thick.