TM 55-1680-317-23&P 2-7. SEWING REPAIRS - Continued Table 2-3.  Stitching Specifications-Continued Recommended sewing machine Component (code symbol) Stitches per inch Thread size OV-1 Aircraft Cold Climate Survival Kit Case MD 7-12 E DN Darn E Carrying strap MD 7-12 E Slide interlocking fastener MD 7-12 E OV-1 Aircraft Overwater Survival Kit Outer Case M D 7-9 E DN Darn E Carrying handle MD 7-9 E Strap reinforcement MD 7-9 E Grommet reinforcement MD 7-9 E Inflation knob retaining strap MD 7-9 E Loop strap MD 7-9 E Slide interlocking fastener MD 7-9 E Inner Case MD 7-9 E DN Darn E Fastener tape MD 7-9 E Retaining line attaching loop LD 7-9 E Life Raft Retaining Line LD 7-9 E SRU-211P Survival Vest Vest LD 8-10 E Edge binding LD 8-10 E Expansion panel LD 8-10 E Fastener Tape LD 8-10 E Loop adjustment webbing LD 8-10 E Seam binding LD 8-10 E Thong BT Bar-tack E Slide interlocking fastener MD 8-10 E BT Bar-tack E Receiver-transmitter antenna cover MD 8-10 E Survival Components Distress marker attaching line BT Bar-tack E Component Pockets MD 8-10 E 2-30