Microflex 6615K SCMU

The Abus Microflex 6615K SCMU is the lock for the everyday bike. It is 85 cm long and 15 mm thick, a steel cable sheathed in overlapping steel shells, locked with a key, and it rides on the frame in its own SCMU bracket so it is always there when you pull up. At 580 g it is light enough that nobody leaves it at home.

How secure it actually is

Abus give the Microflex 6615K Security Level 5 out of 15 on their own scale and pitch it at a low risk of theft. That is exactly the job it does well: the kids' bikes at the school rack, a first bike for the weekend path ride along the Broadwater, the commuter parked outside the café while you grab a coffee. The overlapping steel shells make it considerably tougher than a plain cable lock while it still bends like one, and that is what sends the opportunist looking for an easier bike.

Weight against security

580 g is the sweet spot for a lock that lives on the bike. It is heavy enough to carry real steel around the cable, and light enough to leave fitted to a child's bike all the time. A lock that comes along on every ride protects the bike far more often than a heavy chain sitting in the shed.

What it locks to

The 85 cm length reaches from the frame around a bike rack hoop, a signpost or a verandah post. Pass it through the frame and around something fixed to the ground, and pick up a wheel as well wherever it will reach. Because the shells overlap rather than forming a rigid bar, the lock curls around awkward shapes without fighting you.

Keys and mounting

The SCMU (Snap Cage MU) bracket straps to a seat post, frame tube or rack stay from 15 to 55 mm across, with no tools needed. Once it is on, the lock drops into the cage and comes out again in one movement, so there is no fumbling at the rack. The plastic coating over the shells keeps the steel off your paintwork, both on the bracket and when it is wrapped around the frame.