Ergotron Kit 98-035, Grommet Mount Kit for LX Dual Arm, Rock-solid base keeps monitors in place, Included A grommet mount is included with LX arms 45-245-026, 45-248-026 and 45-295-026. This kit can serve as a replacement, Through surface holes .31" to 2" (8 to 50 mm) wide and up to 3" (76 mm) thick. Ergotron 98-035 easily attaches through a suitable grommet hole. Compatible with LX Dual Side-by-Side Arm and LX Dual Stacking Arm as well as the single-monitor LX Desk Mount Arm Tall Pole.