TM 10-6640-215-13 4-42.  REMOVE/INSTALL THE ANALYTICAL BALANCE AND VIBRATION DAMPING SUPPORT - continued. b.    From  beneath  the  countertop,  remove  six  mounting  screws,  nuts,  and  flat  washers  attaching  vibration  damping support. c.  From each retaining latch, remove two screws, flat washers, lockwashers, and remove the four retaining latches. INSTALLATION 1.  Install Vibration Damping Support.  See figure 4-40. a.  Align and attach four retaining latches to the new vibration damping support, using two screws, lockwashers, and flat washers to attach each latch. b.  Align new vibration damping support on countertop and attach with six mounting screws, flat washers, and nuts. Tighten in place. 2.  Install Analytical Balance and Cover. a.   Place new analytical balance on vibration damping support. b.   Place new cover over analytical balance and fasten in place with four retaining latches and retaining strap. 4-43.  REMOVE/INSTALL GUM BATH/FUME HOOD EXHAUST BLOWER HOSES. This task covers: a. Removal b. Installation INITIAL SETUP: Tools Required General Mechanics Tool Kit, (Appendix B, Section III, Item 2) General Safety Instructions WARNING ELECTRICAL SHOCK Before  performing  any  maintenance  actions  on  electrical  equipment,  ensure  all electrical  power  has  been  turned  off.    Death  or  serious  injury  may  occur  from failure to do this. REMOVAL Remove the Exhaust Hose. a.  The exhaust hose for the gum bath or the fume hood exhaust blower is removed by loosening the screws on the hose clamps at both ends of the hose and sliding defective hose free of the blower discharge and the discharge ducting. 4-114