You can read the recommendations in the user guide, the technical guide or the installation guide for AASTRA 9116. You'll find the answers to all your questions on the AASTRA 9116 in the user manual (information, specifications, safety advice, size, accessories, etc.). Detailed instructions for use are in the User's Guide.
User manual AASTRA 9116
User guide AASTRA 9116
Operating instructions AASTRA 9116
Instructions for use AASTRA 9116
Instruction manual AASTRA 9116
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