Diamondback Sync 4.0 27.5" mountain bike - blue. As new - won in a competition and not something I will use!!
I think it measures as a 18" frame. Please let me know if you have any questions at all.
More details from manufacturer:
Alloy Butted Hydrofomed frame tubing for a lighter, more responsive and durable bike
Suntour XCT-HLO Suspension Forks deliver a smooth ride on varying terrain
Shimano Deore 27speed drive train means a smooth gear shift, even on the most rugged terrain
Tektro Hydraulic disc brakes for precise all weather stopping power
Schwalbe Rapid Rob 27.5x 2.10 tyres, one of the best performing trail tyres available