Apex B.N.A.E. (metric) screwdriver bits. 1/4” Hex Insert Shank and 1/4” Hex Insert Shank with ACR. Also known as French recess bits. The name comes from the Bureau de Normalisation de l’Aeronautique et de l’Espace. Apex’s premium tool alloys and proprietary heat treat help avoid typical problems such as shattering and premature bit wear. Insert bits are commonly used with a bit holder in power tool applications. This combination is economical, provides flexibility and allows a fastener to be magnetically held by the bit. Apex ACR insert bits’ special wing-face ribs grip screw recesses to reduce stripping and cam-out which can result in damage to the surrounding work piece.