TMD Chain Lock keyless smart bike lock with alarm

TMD Chain Lock — the lock you will actually use, every single time

Most good bike locks are a punishment. Heavy, cold, awkward, and guarded by a key you will eventually lose. So the lock stays at home, and the bike stays exposed. TMD Locks started from the opposite end of the problem: build security so effortless that locking up stops being a decision at all.

The result is the first bike lock in the world to combine keyless Bluetooth access, a built-in alarm and independent ART-2 certification. It comes from TMD Security, a Dutch family business that has spent two decades protecting more than 400,000 cash machines from serious, well-funded attacks. That expertise now sits on your top tube — wrapped in soft silicone, in Navy, Beige or Black.

Your phone is the key. There is no keyhole to attack.

Walk up to your bike and the lock recognises your unique digital ID over Bluetooth Proximity Unlock. Your phone never leaves your pocket. One press of the button on the lock body and you are riding.

The deeper benefit is structural. Conventional locks are defeated at the cylinder — drilled, picked, or pulled. The TMD Chain Lock has no cylinder at all, so that entire category of attack simply has nothing to work with. If your phone is flat or forgotten, a personal emergency code entered on the lock button opens it. You are never stranded.

A 100 dB alarm that does the deterring for you

Arm the alarm from the app or with a double press of the button. From that moment, any unauthorised movement triggers 100 decibels of sound — loud enough that a thief working a quiet street becomes the centre of attention. Most bike theft is opportunistic. Opportunists leave.

Layered materials, not brute weight

At 1.7 kg in the 110 cm length, this is among the lightest ART-2 certified chain locks available. That is not a compromise on strength — it is a different approach to it.

• Double-braided technical polyester outer sleeve — resists tearing and everyday abrasion, and stays soft against your frame.
• Dyneema and Kevlar reinforcement — the same high-performance fibres used in maritime rigging and bulletproof vests, giving exceptional resistance to cutting and heat.
• Hardened manganese alloy steel chain — a slimmer, lighter core that stays flexible without giving up resistance.
• Silicone lock body over a polycarbonate housing and a reinforced steel enclosure — shock absorbing, grippy in the wet, and gentle on paintwork.

It coils naturally around a seat post or a rack, and it will not chew through the finish of a bike you paid good money for.

Built for weather you actually ride in

IP57 rated against dust and water: rain, snow, mud and road salt are non-events. The lock is engineered to keep working in hard frost and high heat, and to survive repeated impact — hammer blows as readily as a drop onto the pavement.

The TMD Locks app

• Share access instantly — give a partner, housemate or child digital access without cutting a single spare key.
• Activity log — see when, where and by whom the lock was opened, including shared users.
• Last known location — find where the lock was last used.
• Battery status — around nine months per charge, and a full recharge in two hours.

Available for iOS and Android, free to use.

Choosing your length

• Mini, 70 cm (1.3 kg) — the minimalist choice. Frame, wheel and a slim stand or rack. Ideal as a light everyday lock or a second lock.
• Regular, 110 cm (1.7 kg) — the all-rounder. Enough reach for most street furniture, bike racks and lamp posts.
• Long, 160 cm (2.1 kg) — for cargo bikes, longtails and anyone who wants to lock two bikes together or reach awkward anchor points.

Specifications

• Lengths: 70 cm (Mini), 110 cm (Regular), 160 cm (Long)
• Weights: 1.3 kg / 1.7 kg / 2.1 kg
• Colours: Navy, Beige, Black
• Security rating: ART-2 certified
• Weather rating: IP57 (dust and water resistant)
• Locking: keyless Bluetooth Proximity Unlock, no key cylinder
• Manual override: personal emergency code entered on the lock button
• Alarm: built-in, motion activated, approximately 100 dB
• Battery: approximately 9 months per charge; full recharge in 2 hours
• App: TMD Locks, iOS and Android, free
• Chain: hardened manganese alloy steel
• Sleeve: double-braided technical polyester with Dyneema and Kevlar reinforcement
• Lock body: silicone cover, polycarbonate housing, reinforced steel enclosure
• Warranty: 2 years
• Brand origin: TMD Locks, Almere, the Netherlands

Frequently asked questions

Which length should I choose for my bike?
For a standard city or urban e-bike locked to a rack or post, the 110 cm Regular is the natural choice. If you mainly secure the frame to a fixed stand, or want the lightest possible lock to carry, take the 70 cm Mini. For a cargo bike, a longtail, or locking two bikes together, the 160 cm Long gives you the reach you will otherwise wish you had.

Is it accepted by insurers?
Yes. The TMD Chain Lock is ART-2 certified, which is the minimum standard required by Dutch and most international theft insurers, including ANWB (Unigarant), ENRA, King Polis, Laka, Alteos, Inshared, Be-Insured, Orion, ZLM and Qover. Two practical notes: where the insurer asks for a key number, enter the lock's serial number. And in the event of theft, instead of surrendering two physical keys you export the digital activity log from the TMD app as proof the bike was locked. If your insurer is not listed, check your policy for its position on smart locks and digital evidence.

Does it work with bike leasing schemes?
Yes. ART-2 meets the security requirement of the major leasing providers in the Netherlands and Germany — among them Lease-a-Bike, Athlon Bike, Alphabet Lease, Fisc Free, NFP, Cyclis Bike Lease and Fietslease Holland in the Netherlands, and JobRad, BusinessBike, Deutsche Dienstrad, Mein Dienstrad, Eurorad, Bikeleasing.de and RIDE in Germany. The same rule applies: use the serial number where a key number is requested.

What happens if my phone dies, or I leave it at home?
You set a personal emergency code in the app. Entered on the lock's own button, it opens the lock without any phone present. There is no scenario in which a flat battery on your phone leaves your bike locked to a post.

What does ART-2 actually mean, and what does IP57 cover?
ART is an independent Dutch testing foundation. Its locks are attacked by specialists using the tools thieves genuinely use, and rated on how long they hold. ART-2 is the level normally required for an insured bicycle; ART-3 and above are typically for motorcycles. IP57 is a sealing rating: 5 for dust protection, 7 for resistance to temporary immersion in water. In practice it means Dutch winters, downpours, road salt and a hosed-down frame are all within its design envelope.

How long does the battery last, and what happens when it runs out?
Roughly nine months of normal use per charge, with a full recharge in about two hours. The app shows the battery level, so it is not something you discover at the wrong moment — and the emergency code remains your fallback.

Can it be serviced or repaired?
Every TMD Chain Lock carries a two-year warranty. If something is not right, bring it to us at L'Hirondelle Bike Shop in Meppel — we will assess it in the workshop, handle the warranty process with TMD directly, and advise you on serial number registration for your insurance or lease at the same time. We also stock the lock in all three lengths and all three colours, so you can feel the weight in your hand before deciding.