Kryptonite Keeper 585 Bike Chain Lock, 2.7 Feet Long Heavy Duty Anti-Theft Bicycle Chain Lock with Keys for Bike, Motorcycle, Scooter, Bicycle, Door, Gate, Fence,Black

Looks like a solid lock and chain. Key is "locked" in the lock and cannot be removed until the lock/chain is used again to secure the item (in my case, a bike). I guess a chain cutter can cut it but I doubt that anything else would have an effect.

I appreciate other reviews that mentioned weight and bulk. I had been considering the Keeper 785, but the 585 weighs less than half as much (3.5 vs 1.61 lbs.) and is noticeably less bulky, making a very tidy fit wrapped around my seatpost. Kryptonite's scale of 10 security ratings puts the 585 at 4 and the 785 at 5, so both are in the 4-6 range that their application chart says is suitable for my rural/suburban stops of up to 2 hours. For a lubricant, Kryptonite recommends the same Finish Line Dry product my dealer told me to use on the bike chain, and the lock style is quick and easy to use. I'm very pleased with this convenient deterrent to casual theft while out and about on my bike.

No complaints, using it for around town, not located in a high risk area, and not a very long length chosen at 2.7 feet, easy to snake through, lock and unlock, no issues, happy with this choice.

Looks solid and good price

No Issues Thusfar, Very useful thanks Amazon

So far a great lock

Muy buena seguridad con el producto.

I only used this chain lock a couple times to secure my ebike. It's always been kept inside. I tried to use it recently but couldn't get it open. The key went in most of the way, and it would about halfway. I called Kryptonite customer service and they said try lubricant. If that doesn't work, call Amazon. The return window had closed for Amazon. But the lock is supposed to have a lifetime guarantee. I called Kryptonite back, and a very unfriendly customer service rep told me to fill out a form on their website. Their website is terrible and very intuitive to navigate. I made her help me find it, and submitted it. I got an email in a couple days saying they got the form and to be patient, they're very busy, and will review when they have time.Yeah they're busy, if the locks they sell won't work and people are sending them back. A lock that doesn't work and bad customer service = look around for other bike lock manufacturers.