An orthopedic fastener is designed to attach an implant to bone in such a manner that, until the fastener is tightened, the implant may be rotationally adjusted against the bone. A first active layer for forming a first semiconductor optical device is provided on the first cladding layer in a first area of a principal surface of a substrate. The first and second operational devices may be operatively configured so that both the first and the second output terminals are at a same reference potential during periods in which a magnitude of differential output signal amplitude decreases. The adhesive composition may optionally be crosslinked. The coating material is preferably aluminum oxide. The improved device comprises one or more elastic members that, throughout the working range of diving pressures and volumes, is always elastic and, when pressurized, maintains an internal air pressure that is always greater than the ambient pressure at any dive depth.