Hi,
Yes, Meraki does offer Twinax trunk/uplink cables that are 10 feet long. The Meraki MA-CBL-TA-3M is a 3-meter (approximately 10 feet) Twinax cable with SFP+ connectors. This cable is compatible with various Meraki switches, including the MS350, MS355, MS390, MS410, and MS425
MA-CBL-TA-3M | Meraki Twinax Cable
I am not a Cisco Meraki employee. My suggestions are based on documentation of Meraki best practices and day-to-day experience.
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