Long through-bolts: the hardware solution for thick door handles

When the standard screw length is not enough…

Door handles are generally supplied with standard through-bolts, suited to doors of average thickness (35 to 45 mm). However, certain installations require more robust fixing: entrance doors, armoured doors, insulating doors or doors with decorative cladding. In these cases, the original screw becomes too short to pass through the entire door leaf.

This is where long through-bolts come into play: they guarantee a solid anchor, perfect alignment of the handles and increased durability of the mechanism.

Why choose a long through-bolt?

A long through-bolt is an assembly screw whose threaded shank is designed to pass through the entire thickness of a door, a panel or a set of fittings in order to join two elements together — for example, the two handles of a door handle set.

Unlike a standard unilateral fixing screw, the through-bolt ensures direct axial clamping between the two faces of the support. It passes through the door leaf from side to side and screws into a nut, a threaded sleeve, or the opposite plate of the handle.

Long through-bolts are distinguished by:

  * a length greater than standard (often between 60 and 120 mm depending on door thickness),

   * a regular metric thread, guaranteeing precise alignment of the handles,

   * a countersunk or cylindrical head for a flush fitting,

  * manufactured in galvanised steel, stainless steel (A2 or A4) or brass, ensuring corrosion resistance and long-term mechanical stability.

They are essential for thick doors, armoured entrance doors, fire doors or insulated doors whose structure exceeds the dimensions provided for by standard screws.

A matter of precision engineering

For a designer door handle, every component matters: centre distance, return spring, spindle and of course the fixings.

Long through-bolts in stainless steel, chrome-plated brass or nickel-plated zinc allow you to tighten the handle through the full thickness of the door without any difficulty.

 Result: no deformation, no play in the double handle and a perfect hold of the locking system.

Certain versions are available in lengths of 80 to 120 mm, suited to very thick or armoured doors.

 milla handles: screws and hardware suited to every door

At milla handles, all handle sets are supplied with a complete set of fixings:

  * Through threaded shank in various lengths (10 to 12 cm)

  * Escutcheons and roses adapted to the door drilling,

  * Threaded screws, pins and spacers if required,

  * Decorative fixings matched to finishes (chrome, matt black, satin stainless steel, white lacquered, gold).

Our fixing screws are tested on many different handle models: cylindrical, tubular, contemporary or rustic designs. The correct torque is essential to avoid any play over time. We also offer locking washers, cap nuts and end caps compatible with all types of decorative hardware.

For DIY enthusiasts and installers, there is no need to look elsewhere: milla handles offers you a wide range of screws, nuts, bolts and fixing accessories ready for use, perfectly suited to your hinged, sliding or French doors. A complete assortment for screwing, pressing, welding or fitting your handles and ironmongery with precision, whatever the material type – from wood to galvanised sheet metal.

Whether your project involves a designer front door, an interior sliding door, or a rustic wooden door, you benefit from a complete and reliable fitting kit, ready to install with a simple screwdriver. We ensure compatibility with all wooden, steel, glass or aluminium doors, for solid assemblies and smooth operation over time.

Long through-bolts are an indispensable technical solution for a durable and precise installation of handles on thick doors.

By choosing milla handles, you benefit from a complete service: designer handles, handle screws suited to all door types and decorative hardware of European origin.

No nasty surprises, no parts to source elsewhere: everything is included, down to the last millimetre, for an easy and lasting installation!