0033 00  TM 10-1670-287-23&P  UNIT MAINTENANCE  MC-4 RAM AIR FREE-FALL PERSONNEL PARACHUTE SYSTEM  MAIN RISERS  THIS TASK COVERS:  INITIAL SETUP:  Tools Materials/Parts  Personnel Required  Equipment Condition  Follow-Up Procedure  REPLACE NOTE Needle, Tacking (Item 29, WP 0063 00)  Shears (Item 39, WP 0063 00)  Wrench, Open End, $^{7}$/$_{16}$-IN. (Item 45, WP 0063 00)  Riser Set, Main, 3-Ring (Item 11, WP 0065 00)  Tape, Lacing and Tying (Item 33, WP 0076 00) Lay out on packing table or other  suitable area.  92R (10) Parachute Rigger  Initial receipt (WP 0006 00) •  Replace  Risers will be replaced in pairs.  1.  Remove overhand knots on rear riser control toggles.  Change 1  0033 00-1  Guide Ring Control Line Toggle Ring Control Toggle Overhand  Knots 