The PAL6035 is a PIN heatsink. The heatsink is made up of 289 tightly pack pins. They are packed so tight there is barely enough space for the mounting clip to fit! The use of pins increases the surface area. By packing so many pins so close together, the PAL6035 has more than twice the surface area of a normal heatsink of similar size and that's the secret to its cooling power.
Here is a base shot of the PAL6035. Notice the copper base plate and lack of plastic pegs. Copper transfers heat faster than aluminum. However copper retains heat longer. Aluminum on the other hand transfers heat at a slower rate but can get rid of it quicker than copper. What Alpha did was combined the best of both worlds. By using a copper base plate the heatsink can transfer heat off the CPU core faster. The base plate transfer its heat to the aluminum heatsink which quickly gets rid of it.
Without the plastic pegs, the PAL6035 will have no problems fitting onto an AMD Thunderbird or Duron processor. For an Intel Coppermine CPU, Alpha supplied some stick on rubber pegs. They even went so far as to engrave circle markings to show where the pegs go. The use of the rubber pegs ensures flush mounting of the PAL6035 to any Coppermine of Celeron II CPU.