Here is a sturdy, well built compact super-telephoto 500mm lens that will fit in a small bag. It is a unique, well built lens with beautiful image quality that utilizes a series of reflecting mirrors to make the lens more compact and lightweight.
Unlike most mirror lenses, there are two internal ND filter options that allow you to stop down.
This would be a great lightweight telephoto addition to your kit. I also read somewhere that this lens is great for portrait work as it gives a beautiful ring blur that accentuates your lighting choices and highlights the subject.
It has a universal interchangable "T" mount with M42 threading.
This lens is in excellent condition with minimal wear and works perfectly. The glass and mirrors are clean and scratch-free with no haze, fungus or separation. The mount is secure. The focus is very smooth.
Tripod collar and lens caps are included. This is a nice one.