Square Key Clamp Long Tee for 25 x 25mm Box Section, Galvanised

The square key clamp long tee joins two square tubes at 90° with a long barrel, typically a vertical post to the top rail on straight and level frames. One tube passes through the long barrel and the other pushes into the side socket; hex socket grub screws lock both. It suits 25 x 25mm square box section and is galvanised mild steel for indoor and outdoor use, so square tube frames can be built without welding. The price shown is for one fitting, with a minimum order of 5.

Why use a square key clamp long tee

A longer grip on the through tube. The long barrel holds the through tube over a greater length than the short tee, for a stiffer joint.

No welding. Square box section frames go together with a hex key and can be taken apart, altered or extended later.

A clean, modern look. Square section suits architectural handrails, shop fitting, display frames and furniture where a round tube would look out of place.

Galvanised for outdoors. The zinc coating protects the steel in yards, gardens and outdoor frames.

Where it is used

Square section handrails and balustrades, shop fitting and display frames, benches, tables and workstations, shelving and storage frames, garden and outdoor structures, and any frame built from 25 x 25mm box section.

Specifications

Letters refer to the dimension drawing above. Dimensions are for guide only and may vary slightly.

Know its limits

It fits 25 x 25mm square box section only; it will not grip round tube or other square sizes. No load rating is published; for a frame that must carry a set load, ask a structural engineer to check the design.

Which 25 x 25mm square fitting?

How many do you need?

One at each joint of this type. Sketch the frame, mark each joint and count the fittings for each type before you order.

Choosing the right size

Square key clamps are sized by the outside of the box section. Measure across the flats of your tube: this fitting suits 25 x 25mm. The same fitting is made for 40 x 40mm box section.

Fitting and care

Cut the box section square and deburr the ends. Slide or push the tubes into the fitting, set the frame square and tighten the grub screws firmly with a hex key. Check the screws after the first week and once a year after that. Touch up scratched galvanising with zinc-rich paint.

Frequently asked questions

Ordering and delivery

Order 5 or more online, with Express UK Delivery to your site and same-day dispatch on orders before 2pm, Monday to Friday. For a full frame kit, call 01744 520 110 or email sales@industrialsuppliesco.co.uk and we will confirm availability and delivery before you order.