Steel and elastomer assembly that has a central through-passage equal to or greater in diameter than the riser bore and that may be positioned in the riser string to reduce local bending stresses.
The Mazatec people are an indigenous people who inhabit an area known as the Sierra Mazateca in the state of Oaxaca in southern Mexico, as well as some communities in the adjacent states of Puebla and Veracruz.
The Toltecs were a warlike society ruled by priest-kings. By 1150, their civilization went into decline and Tula was eventually destroyed and abandoned. The Mexica (Aztec) culture considered ancient Tollan (Tula) the high point of civilization and claimed to be descendants of the mighty Toltec kings.