For releasing the cable, you need to loosen the screwnut at the bottom of the reel, hang the cable inside the hook, and let the camera probe out of the reel, then you can easily draw the cables out. If you need to lock the cable when you find the target, you can tighten the nut to hold the cable; For retracting, just roll the cable back, and put the camera probe back to the reel. 

Yes, the fiberglass cable is hard and stiff enough for long-range inspection, while the camera probe maintains flexibility for accessing turns and bends. 

The diameter of the camera is approx 0.9in, so it works on pipes larger than 0.9 inches, as long as you can put it in. I used it to inspect about 30 feet of 2.5” piping that was a straight run with no bends. 

Yes, you need to wear headphones to record the voice.