Four nylon wheels Wheeled Roller Centralizer

Four nylon wheels Wheeled   Roller Centralizer for sucker rod 1. Roller Centralizer should be installed:   1) On the first two or three rods above the bottom hole pump.    2) Intermittently throughout the rod string where wear is indicated on rods or tubing.    3) Where known hole deviation occurs.    4) On the first two or three rods below the stuffing box.   2. Tech Parameter   Specification DIMENSIONS(INCH) Diameter Length Length of the groove 5/8''ROD/2-3/8''TUBING 1.50 27 1.80…