This is a 5 Manual Lot on the HT 100, 101 Workshop Service Manual and Parts List Manual, Telescopic Drive Tube Workshop Service Manual, HT Gear box Workshop Service Manual and the Power head Workshop Manual. The 4180 service manual has 64 pages in it and the Parts Manual has 33 pages. The Telescopic Drive Tube Workshop Service Manual has 11 pages. The HT Gearbox Workshop Service Manual has 15 pages. The Power head Workshop Manual has 48 pages. You will see that the 4180 is the Service Manual with this. This is the service manual that STIHL says is for this saw. The Service Manual shows you how to actually work on every part of the equipment. The Parts Manual shows you with an exploded diagram of every part to the equipment and a part # for each part with a name. You will not have to depend on someone else's knowledge when ordering parts. These manuals will help you do you own work on your equipment. This is actually made out of paper/book/magazine. You will receive the manuals as pictured.