TM 10-1670-296-20&P                                                    0006 00 0006 00-12 Table 2.  Preventive Maintenance Checks and Services – continued B – Before D – During A – After INTERVAL ITEM NO. B D A ITEM TO BE CHECKED   OR SERVICED EQUIPMENT NOT READY/ AVAILABLE IF: 20 Clevis Cover.  Inspect cover for loose or broken stitches, tears, broken grommets, or foreign material. Cover has loose or broken stitches, tears, grommets are broken, or foreign material is present. 21 Single Knife Parachute Release Strap.  Inspect strap for loose or broken stitching, cuts, worn and frayed webbing, or presence of foreign material.   Check knife and fastener for rough areas, bends, breaks, and cracks.  Check knife-edge for sharpness.  Ensure that ferrule operates properly. Strap has loose or broken stitching, cuts, worn or frayed webbing, or foreign material is present.  Knife or fastener has rough areas, bends, breaks, or cracks.  Knife-edge is dull. Ferrule does not cover the safety aperture when unscrewed to the full open position.