SLY2X 2x T-Mount

This light-weight precision Bower 2x Autofocus Teleconverter attaches directly to any Pentax Autofocus Mount body and will double the focal length of the primary lens being used. If you have a standard 50mm lens on the camera, this makes it a 100mm lens. If you use it together with a 70-300mm zoom lens, it becomes a 140-600mm zoom lens. It functions perfectly with the autofocus mechanisms of your camera as long as the maximum aperture on the primary lens is f4 or wider. If the aperture is slower, the in-focus lights will work but focusing must be done manually.