Thermalright SILVER ARROW IB-E CPU Heatsink for Intel LGA 2011-1366-1155-1156-1150-775 & AMD Socket FM2-FM1-AM3 plus -AM3-AM2 plus -AM2 Mfr Part Number: SILVER ARROW IB-E Features: Double fin design&#44; each side with 154 x 120mm heat dissipation area&#44; can be used with 14 or 15 Special Arrow fin design&#44; which allows cool air to pass through and take heat away rapidly&#44; effectively