OnGuard Mastiff 3.5 ft Chain Lock with Integrated Key Lock – 10 mm Hardened Steel Hex Links (110 cm / 3.57 ft) – X2P Double Bolt Lock Head, Z-Cylinder Core, 5 Keys

A touch heavy, still a great lock. LOVE the extra length. I carry mine in a basket so the weight does not bother me.

The 10mm chain is substantial. The padlock size took me aback when I first unwrapped it. The lock mechanism is smooth and easy to use. I like that the lock has a rubber coating on the U portion. I was somewhat surprised by the amount of plastic sheathing on the lock, but it does appear sturdy. I bought an OKC noose chain to go with (my Scouting unit often goes on group rides to the movies, etc., so this extends the group coverage while we're inside). The OKC links are narrower, but do slide over the lock (displacing some of the rubber coating). The OnGuard chain is robust. I could slide the nice cover enough to check all the link welds which looked good. Hoping to get many an event-free year with this lock and chain. Nothing will deter a determined thief, but this will at least divert attention elsewhere. When we go away, the lock and chains are used to secure our bikes to the floor anchor.

This lock is no joke. The chain is heavy and there is no denying that. The lock is a bit silly in my opinion. The key doesn’t easily slide in and it’s very ambiguous as to whether it’s locked or not (click feel when turning key). The key doesn’t come out when it’s unlocked - which is very clear - but I would rather have a more traditional @click - it’s locked” type of feel.

I've had this for several years and LOVE it! When I have to leave my bike on my rack in truck I leave this on it and feel 100 secure cause it's a huge beast. It's REALLY heavy and it is awkward but it's worth it to know it's locked up safe. I spent hours reviewing bike locks and chains before buying this and a big time review in NYC couldn't get through it even with battery powered tools. And it's not even expensive considering what it is.

Like carrying a tow chain. I will only use this when my bike needs to be left outdoors. Not something you’ll carry on a ride. But, it’s what I expected and definitely serves its purpose. Don’t buy it if you are expecting it to be light.

Great lock. Only reason i gave 4/5 is because it’s very heavy. Which means secure? Lock and keys work very smoothly and its big enough to both protect your bike or yourself:)

Great lock very hard to cut even with 4 feet bolt cutters

Great lock, however way to heavy 10 pounds for the weight of this bike lock.