Rank #10 in Best Bike Locks 2026: 10 Ranked, Diamond Beats Gold on Price
Kryptonite Combo U-Lock, 12 mm Shackle, 4-Digit Code
Price and rating as shown on Amazon when we collected them. Both change.
The Kryptonite Combo U-Lock is the cheapest of the ten locks in this guide at £18.03, and it is the one that makes the price-per-millimetre argument plainest. Its shackle is 12 mm of hardened steel. The £299.99 Hiplok at the other end of the list claims 32 mm — 2.7 times the steel for 16.6 times the money. The Kryptonite does that without a key, on a 4-digit resettable combination.
The figure that does not sit right is the Anti-Theft Protection Offer: this listing quotes it at 'up to $500', in dollars, on a page priced in sterling. The £38.75 Kryptolok in the same guide quotes the same Kryptonite programme at £1,000, in pounds. Both are Kryptonite's own numbers; only one of them is in the currency you are being asked to pay in. Everything on this page is taken from the Amazon listing — price, specifications and reviews — and not from any test we have run.
How those 1,069 ratings break down
An average hides its own shape. This is the spread behind the 4.3 stars.
Specification
Exactly as published on the Amazon listing, field for field.
| Price | £18.03 |
|---|---|
| Customer rating | 4.3 out of 5 from 1,069 ratings |
| Shackle | 12 mm hardened steel, the thinnest of the ten picks |
| Locking mechanism | 4-digit resettable combination, no keys |
| Interior / exterior dimensions | 4" x 8" / 6.5" x 9.5" |
| Anti-Theft Protection Offer | Up to $500 upon registration, quoted in dollars on a sterling listing |
| Best Sellers Rank | 12 in Cycling U-Locks |
| Control Method (as listed) | Touch |
What buyers actually say
Quoted from customer reviews on Amazon
Verified purchase“It works really nicely.It opens by tilting to the side; maybe that makes it more secure.I LOVE not having to remember a key but getting the security of a D lock/U lock.”
Verified purchase“Great locks, luckily I haven't had to try them against a theft, but the seem like good quality and aren't too heavy as well as easy to use.”
What it is up against
The rivals it was ranked against in Best Bike Locks 2026: 10 Ranked, Diamond Beats Gold on Price.
Questions people ask
Does the Kryptonite Combo U-Lock need a key?
No. The listing describes an easy-to-use 4-digit resettable combination and states there are no keys for you to lose, and the spec field lists the lock type as a combination lock.
What are the dimensions of the Kryptonite Combo U-Lock?
The listing gives a 12 mm hardened steel shackle, interior locking dimensions of 4" x 8" and exterior locking dimensions of 6.5" x 9.5".
What happens if I forget the combination?
Kryptonite's Combo Safe Program lets you register your unique 4-digit code on the Kryptonite website, after which the customer service team can help. The listing does not say what happens if the code was never registered.
How much is the Anti-Theft Protection Offer worth?
The listing states up to $500 reimbursement upon registration — a dollar figure on a product priced at £18.03. The £38.75 Kryptolok in the same guide quotes the same Kryptonite programme at £1,000 in sterling.
What can I use the Kryptonite Combo U-Lock on?
Kryptonite lists bicycles, sports equipment, gates and fences, tool boxes and ladders, grills and lawnmowers, skateboards and truck beds.
How is the Kryptonite Combo U-Lock rated?
4.3 out of 5 from 1,069 ratings, and it sits at number 12 in Amazon's Cycling U-Locks best sellers rank. The breakdown shown on the listing has 71 five-star entries against 7 one-star.
Comments
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