Wonderful 4F21-AL-3

Modular transtibial and transfemoral builds use a tube clamp at the pylon connection.

Limb length is established at this fitting, so it carries the adjustment that matches a prosthesis to the contralateral side.

Toe-out and toe-in are set by rotating the pylon within the clamp before tightening.

Alignment revisited during rehabilitation depends on a clamped joint that can be loosened and reset.

Long residual limb and knee disarticulation fittings depend on build height, since space between components is limited.

Higher loads are commonly carried on 34 mm pylons, so the diameter the clamp accepts bears on which users it suits.

Clinics holding stock benefit from clamps matched to the pylon diameters and build heights they routinely fit.

Two Adjustments at One Fitting

Limb length and rotation are both established at the clamp and locked by the same screws.

Length Set at the Bench, Not at Manufacture

A clamped joint allows the final distance between socket and foot to be established and revisited.

Rotation Set Before Tightening

Turning the pylon within the bore sets toe-out or toe-in, which affects how the foot meets the ground at every step.

Grip Across the Contact Area

Closing the slot reduces the bore and grips the tube by friction over its full contact length rather than at one point.

Adjustment That Can Be Revisited

Alignment changes during rehabilitation are accommodated by loosening, resetting and retightening to torque.

Heights for Constrained Builds

A range of build heights addresses fittings where space between components is limited.

Light at a Point Well Down the Limb

Aluminium keeps mass down on a component sitting low in the build.

A Harder Anodised Surface

Anodising gives better corrosion resistance than bare alloy on a fitting exposed to weather and floor-level dirt.

Insertion Depth Established

Minimum pylon engagement is confirmed, so the clamp grips over the length the design intends.

Torque Taken From the Instructions

The screw figure comes from this product's documentation rather than from comparable clamps elsewhere.

Supply and Documentation Arranged

Medigear.uk can arrange supply, documentation and the provision of consumables.

Aluminium Tube Clamp Adapter

Joining a pylon to an adapter in a modular lower limb prosthesis.

Item Reference: 4F21-AL-3

To be confirmed against the manufacturer's marking, including the meaning of the trailing digit.

Manufacturer

Wonderful Rehabilitation, to be confirmed at quotation.

Material

Aluminium alloy, with the alloy to be confirmed.

Finish

Black anodised, per the item shown, to be confirmed.

Tube Diameter Accepted

Confirmed at quotation, with 30 mm and 34 mm both in common use.

Build Height

Confirmed at quotation, including which height this variant corresponds to.

Heights Available

Confirmed at quotation across the range.

Clamp Slot and Screws

Slot closing onto the tube, with screw size, count and type confirmed at quotation.

Clamp Screw Torque

Confirmed at quotation from the manufacturer's instructions.

Minimum Tube Insertion Depth

Confirmed at quotation.

Rotation Adjustment

Range and locking method confirmed at quotation.

Proximal Connection

Pyramid, receiver or threaded face, confirmed at quotation.

Maximum Body Weight

Confirmed at quotation for this reference and material.

Product Weight

Confirmed at quotation.

Compatible Pylons and Adapters

Confirmed at quotation.

UKCA or CE Marking and Declaration of Conformity

Issued by the manufacturer and requested from the seller at quotation.

Instructions for Use

Provided by the seller at quotation, and required before fitting.

Warranty Terms

Set by the seller at quotation.

The 4F21-AL is an aluminium tube clamp adapter, joining a pylon to an adapter in a modular lower limb prosthesis. Two of the measurements that make a limb fit one person are established at this fitting. Length comes from how far the pylon enters the bore, which is why a clamped joint is used rather than a bonded one: the distance between socket and foot is set at the bench and revisited as rehabilitation progresses. Rotation comes from how the pylon is turned before the screws are tightened, setting toe-out or toe-in and with it how the foot meets the ground at every step. The clamp achieves that through a slot that closes as its screws are drawn up, reducing the bore slightly and gripping the tube by friction across the contact area, which is why both the torque figure and the minimum insertion depth matter and why both should come from the manufacturer's own instructions rather than from comparable fittings. Tube diameter decides compatibility, build height decides what can be assembled around it, and aluminium with an anodised finish keeps the component light and protected low in the build. Cutting, setting and tightening are the work of the prescribing prosthetist. Those figures are provided by the seller at quotation alongside UKCA or CE documentation. Medigear.uk lists the clamp for UK business buyers and can arrange supply, documentation and the provision of consumables. Enquire for a written quotation.