Cummins Diesel Engine Service Manual. Serial Numbers Covered – Not Specified. Models Covered – H HS HR HRS – NH NHS NHRS – NHH NHHS NHHRS – NT NRT. Number of Pages – Approx 1/2 Thick, but numbered by chapter. Overall in good useable condition, there may be some smudges or fingerprints, yellowing pages, handwritten notes, stains, and general wear, but that’s because these things get used and referenced over the years. Packed full of great information and specifications to get your favorite machine back in operation! Many other items found in my store, if you need something specific, just ask. Feel free to ask a question if you have one, I’ll get back to you!