60W L-Tip Compatible MacBook Pro/Air Charging Cable 5 Pin Magnetic Charging for MacBook Models Prior to June 2012, 1 .8M

First off, I gotta remark on how well this cable was designed -- it looks exactly like something Apple would make, right down to the texture of the cable jacket. The weight and rigidity of the cable, as well as the strain reliefs at each end, are also identical to Apple's.But it's not looks that are important, but function: and so far, it works perfectly with my old 17" MacBook Pro (the last one they made in 2011). I bought this so I could power my MacBook via USB-C power bank (an Anker Prime 27,650mAh with 140W output) instead of having to be tied to a wall outlet.The first USB-C PD adapter I used this cable with (capable of supplying 100W), the LED kept flashing on and off, and the computer kept showing charging, unplugged, charging, unplugged, and so on. I assumed it was the cable at first, but then I tried it on another USB-C PD adapter, and it worked fine.So if your cable blinks on and off like this, it's not a bad cable, it must be some "confusion" with the PD circuit trying to negotiate the voltage output -- just try another power adapter. And make sure it's one of the large ones that are explicitly labeled "PD" (just because it has a USB-C jack doesn't mean it's the same thing).I've been using this for a few weeks, now, and it has proven to be a very good buy.