Vehicle Restraint – 503 Power Lock Surface Chock (Manual Restraint)

The 503 is a manual vehicle restraint system that prevents premature vehicle departure or “drive off” and “creeping” of a vehicle or trailer to avoid unsafe situations.

The Holdfast Loading Systems manual vehicle restraint system locks vehicles or trailers onto the loading bay to create a physical lock onto the trucks wheels, helping to prevent untimely vehicle departures.

Advantages of the 503 Power Lock Surface Chock
Key Features

Advantages of the 503 Power Lock Surface Chock

• High locking arm height (420mm) provides optimum protection from vehicles ability to drive off when locked.
• Engineered for easy unlocking from the vehicle wheel even if under load.
• Wheel detection system ensure an audible alarm will sound inside the building should the lock be released prematurely.
• Suitable for practically all types of trucks
• Can be linked to existing dock & door controls.
• Robust design & galvanised construction
• Locking arm designed to slide between the wheel and mudguard without damaging the mudguards.
• Easy Installation
• Maintenance friendly
• The restraint acts also as a wheel guide helping ensure the vehicle is centred avoiding damage to building, truck and dock equipment.
• In the event of a power failure, the restraint can be manually unlocked to release the truck.

•Locking arm can be rotated (in lateral direction) by means of a hand lever to the horizontal position in front of the wheel.
• When the wheel sensor does not detect a wheel then the acoustic alarm on the control box will sound to warn the operator that the vehicle is not locked on correctly


The 503 Manual restraint system restrains almost any truck or trailer with a wheel diameter of btw 650 – 1200 mm. The space between the 2 wheels or between mudguard and wheel must be at least 60 mm. This space is required for clearance of the rotating locking arm.


240VAC, 50 Hertz


The 503 Vehicle restraint system is manually operated via an extendable lever for easy engagement of the locking arm on the truck or trailers wheel. A set of traffic lights interlocked with the 503 operation clearly indicate if the locking arm is correctly positioned and locked ready for unloading/loading to proceed.

Vehicle Restraint – 503 Power Lock Surface Chock (Manual Restraint)

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