Kryptonite Evolution Series 4 Bicycle U-Lock with Disc Lock Technology - High Security Bike Lock for Urban Commuters (Yellow) - Perfect for City Riding, Bike Parking & Theft Protection

Specifically bought this in YELLOW to show any potential thief what he has to contend with. Heavy duty. The U-bar is quite fat in diameter which is also a discouragement. I wanted little space in-between the lock body and top of hook. This is perfect if you are using a fat type security cable which I recommend the Kryptonite Kryptoflex 3/8" (10mm) in 7 foot. I have two neighbors who use heavy chains which added another 9 lbs. to their e-bike. I felt wayyy too much. The Kryptoflex cable weighs almost ONE lb. only! Also, they have to wrap all that bulk chain around the bike body. Heavy, unsightly. The cable is plastic coated and can be wrapped around any part of bike tightly. Also, one end of cable can be pulled through the other end loop to extend the length if you are wanting to keep your precious bike finish farther away from whatever you are securing it to. The lock is well coated also and will protect your finish. I like the fact that it came with 3 keys and especially an insurance policy (at a small cost, $29) if you register your lock and bike. In the event that the lock itself was compromised leading to the theft, you can put a claim in. (Most likely will have to have a police report as proof).In any event...locks, cables, chains are mostly a deterrent. If a thief is that determined he can and will do anything. "Where there is a will, there is a way." But this lock and cable combo will surely make him think twice!Apparently every lock can be picked, but this is one heavy duty lock. I’m assuming I will avoid those who can pick it as a rule. The only hard thing about it was the rubber coating around the loop bit. It didn’t want to fit through my chain, but after a couple of times, it now is much easier to get onto the chain. I like the rubber around the metal. I also like the fact that the entire loop comes detached from the thick bar for ease of locking it through the chain. Very happy with this purchase.Not sure how much I can contribute here, but it is definitely a big, robust lock. It is surprisingly lightweight, but still seems solid. No, I have not taken an angle grinder to it, and my lock picking skills are not up to par for a proper test so I can't comment on actual security, but I feel it is a good match for my Schlage 12MM cinch chains. It is plenty to keep from being an easy target.I also appreciate it comes with 3 keys.Rubber cover over the shackle does not appear to be described in product dimensions. I had to cut off small portion to fit it through a 5/8 inch chain opening.I used the lock to couple a heavy chain to a floor shackle inside a garage. Works fine, looks appropriately intimidating.Does exactly what I needed to, bike doesn’t move when it’s locked upI bought this lock specifically to use as the locking link for a Schlage 12mm cinch-ring security chain. As with most Kryponite locks, it is tough and well made.This Kryptonite/Schlage chain combo is primarily for securing our mountain bikes on my truck during one of those bike trips that I end up parking and leaving the truck at public places for an errand or something. Keep in mind though, this or any other brand of lock/chain combo isn’t foolproof where you lock your bike on a lamppost and leave it overnight on the street. To a determined thief there’s no such thing as an unbreakable lock or chain.That being said, this lock/chain combo should be tough enough and prove to be difficult for a thief to make a quick steal of your bike, especially if it’s on a visible high-traffic location. The combo is also intimidating enough to discourage these criminals and look for a target elsewhere.This is an awesome disc lock for motorcycles! It's small enough to be carried around easily, but burly enough to look and feel solid when locked on the bike. I use it to attach my chain to the bike in bad parts of town, and I also use it just by itself when I'm on the go and don't want to carry a chain. I like the yellow color because it's bright enough to act as a deterrent, in addition to making my bike more of a pain in the rear to steal. It comes with three keys (one lighted) and all work great, plus it has a unique serial number so you can have new keys made in case these are lost. The lock mechanism is smooth and easily accessible (a BIG plus if you've ever messed with disc locks before) and I just lube it every couple weeks and it been quiet and efficient. The shackle is nice and wide, so it will fit around most discs on most bikes and still have space to add a chain, but its also very thick (good for resisting cutting) but trouble if your disc has only small holes in it. That being said, I can also throw this around the rear sprocket with no issues, and the rubber coating is nice and protective so it doesn't damage the bike.This has become something I use several times a day and love it so far, I will update this review if issues arise in the future.I initially did a lot of searching for a sturdy padlock for the mountain bikes. I was a little confused at first as it seemed to be for the locking of brake rotas on motorbikes but decided to take a chance.Well worth it, very robust with a lovely black soft plastic coating. Main key is as sturdy as the lock with a useful blue light. Using in conjunction with a Kryptonite cable which is a great combo and finished off with a ground anchor when using it in the garage.Highly recommend it for the security of mountain bikes - on the bike racks when leaving the car parkedNote: It is very heavy so I would not want to carry it around on a backpack , there are better suited mobile bike locks for that purpose.I like this padlock/U lock!Heavy nicely finished lock. Can’t review how well it performs as no attacks as yet.Excellent! Just had to trim a small piece of plastic from the shackle, to allow it through the vented disc.Easy to operate and the light on the key is a nice feature