The fixed driver is to be used with the appropriate bit driver needed for screw removal. The bit driver can be inserted into the fixed driver by compressing the adaptor collar and inserting the appropriate ¼” square or AO driver. The bit driver can be removed from the fixed driver by compressing the adaptor collar.

Заранее признательна за любую помощь!

AO type screws and plates have, for many years, been the human and veterinary standard implants.
They were originally designed in the 1950s by the AO study group [Arbeitsgemeinschaft fuer Osteosynthesefragen (English: Association for the Study of Internal Fixation, AO/ASIF) ] which continues to this day to lead the world in implant design.
http://www.veterinary-instrumentation.co.uk/skin1/admin/UserFiles/File/2016 catalogue/MAIN CATALOGUE/J84818_VETS 2016 LOREZ PRICES.pdf

1958 hat die AO/ASIF (Arbeitsgemeinschaft fuer Osteosynthesefragen) vier Grundprinzipien1 erarbeitet, die zu Leitlinien fuer die Osteosynthese wurden.

см. там же
Handstueck, mit AO-Kupplung
Schraubenziehereinsatz, mit AO-Kupplung
http://synthes.vo.llnwd.net/o16/LLNWMB8/INT Mobile/Synthes International/Product Support Material/legacy_Synthes_PDF/016.000.131.pdf