The PM-33 fits binding post sizes up to 8mm. This patented spade lug is made from ultra-pure copper. A unique feature of this connector is the compressible wafer between the contacts, which maintains dynamic pressure on the binding post. This prevents an increase in impedance due to vibration or temperature changes. Pressure ridges ensure a gas-tight contact and dramatically reduces contact resistance. The plating is Kimber's proprietary Ultraplate™ finish. Comes with silver solder and Kimber HeatShrink.