Archrock provides natural gas compression services to oil and gas producers, midstream operators, and pipeline companies across the U.S. Natural gas compression increases gas pressure so it can flow through gathering systems, pipelines, and into processing or storage facilities. Archrock's core business — roughly 85% of revenue — is contract operations: Archrock owns, installs, operates, and maintains compression equipment at customer sites, charging customers a fixed monthly fee per horsepower rather than having customers own and staff the equipment themselves. The fleet consists of approximately 5,300 compressor units totaling about 4.8 million horsepower, deployed roughly 60% in gathering and processing applications and 40% in gas lift applications. Archrock's secondary business (~15% of revenue) is aftermarket services — selling parts and providing maintenance, overhaul, and repair to customers who own their own compression equipment. Archrock's revenue is driven by operating horsepower and the monthly rate per horsepower. Because customers supply the fuel to run the compressors, Archrock has limited direct commodity price exposure. Archrock has been shifting its fleet toward large horsepower units, which stay on location longer, require fewer technician visits relative to output, and carry higher margins. Archrock sells to roughly 300 customers, with no single customer exceeding 10% of revenue. Growth is driven by new-build large horsepower investment under firm customer contracts, systematic sale of smaller older units, and acquisitions.