The nPowerTek NPH-1366-140HC heatsink is intended for socket LGA1366 Intel processors up to 130W TDP. On the inside of the NPH-1366-140HC heatsink is a hollow copper heat column and surrounding this, a bog-standard bifurcated aluminum fin extrusion. The heat column functions essentially like a large heatpipe, you can see the inside of one in our review of Intel's FCLGA4-S reference heatsink. The copper heat column is 33mm in diameter, with the inner surfaces covered by a sintered metal wick and the contents under vacuum.