I have the Profix single pin sight and really love it. It is the brightest pin I have seen. It has 3 ft. of fiber optic wrapped around the spool. My only complaint is that the plastic covering ( almost like tape) came off from around the spool. I am going to try and use some laminating plastic and melt it on. That should hold it. But it is a very nice sight. Very light but sturdy and as bright as can be.