Copper Tube Butt Splices

Copper tube butt splices are crimp connectors that join two cables end to end in a straight line, giving a strong, low-resistance in-line joint. Our range of Unicrimp copper butt splice terminals runs from 1.5mm² and 2.5mm² right up to 50mm², 70mm² and 95mm², with 4 to 6mm², 10mm², 16mm², 25mm² and 35mm² sizes in between.

Smaller sizes come in packs of 25, larger ones in packs of 5 or 10. Order on a trade account at trade prices, and have stock lines delivered the next working day across NI and ROI when you order before 5pm.

QB1-5 In-Stock

Unicrimp Copper Butt Splice Terminal 1.5mm

£0.07 inc. VAT

QB10 In-Stock

Unicrimp Copper Butt Splice Terminal 10mm | Pack of 10

£1.92 inc. VAT

QB16 In-Stock

Unicrimp Copper Butt Splice Terminal 16mm | Pack of 10

£3.00 inc. VAT

QB25 In-Stock

Unicrimp Copper Butt Splice Terminal 25mm | Pack of 5

£3.30 inc. VAT

QB2-5 Ships in 3-5 days

Unicrimp Copper Butt Splice Terminal 2.5mm | Pack of 25

£3.90 inc. VAT

QB35 In-Stock

Unicrimp Copper Butt Splice Terminal 35mm | Pack of 5

£4.20 inc. VAT

QB4-6 In-Stock

Unicrimp Copper Butt Splice Terminal 4-6mm | Pack of 25

£3.48 inc. VAT

QB50 In-Stock

Unicrimp Copper Butt Splice Terminal 50mm | Pack of 5

£4.30 inc. VAT

QB70 In-Stock

Unicrimp Copper Butt Splice Terminal 70mm | Pack of 5

£8.83 inc. VAT

QB95 In-Stock

Unicrimp Copper Butt Splice Terminal 95mm | Pack of 5

£11.23 inc. VAT

How to choose and fit butt splices

Butt splices are used wherever a cable needs extending or repairing in line, from control wiring to large power cables. Choosing the right size and crimping it properly is essential for a joint that lasts.

Selecting the size

Each splice is marked with the conductor cross-sectional area it is designed for. Match it exactly to the cable:

1.5mm² to 6mm²: lighting, small power and control circuits
10mm² to 25mm²: submains, larger radials and equipment supplies
35mm² to 95mm²: distribution and heavy power cables

If joining two different sizes, use a reducing splice or a different method, as a standard butt splice is designed for equal conductors.

Crimping correctly

Strip each conductor to half the splice length, insert fully so the ends meet near the centre, and crimp each side with the correct die. Smaller splices can be crimped with a hand tool, while larger sizes generally need a hydraulic crimper. Choose a matched tool from our strippers and crimp tools range and inspect the finished joint for full compression.

Insulating the joint

Copper tube splices are uninsulated, so the finished joint must be insulated. Slide heat shrink onto the cable before crimping, then position and shrink it over the splice with suitable overlap. For armoured cable in the ground, a full SWA cable joint kit provides the necessary mechanical and moisture protection. For terminating rather than joining, see our cable lugs.

Compliance

Crimped joints made with the correct tool are widely regarded as a reliable method of joining. Check current wiring regulations (BS 7671) regarding the accessibility of joints and the manufacturer's instructions.

Meteor Electrical stocks 5,000+ products from over 100 trade brands at our Cookstown warehouse. Free delivery applies over £30 / €35 ex VAT, and Click & Collect is available from our trade counter.

FAQ's Ask Your Own Question

What are Butt Splices?: Butt splice connections are a typical method of connecting two wires. Butt splices feature a high level of connection, which allows the electrical current to flow freely. They're a quick and easy way to make or repair an electrical connection between wires.
What are Copper Tube Butt Splices?: Copper tube splices are used to join wires of the same size. The installation of a butt connector improves the safety and longevity of the connection.
What tool do I need to crimp a copper butt splice?: Small butt splices can be crimped with a ratchet hand crimper using the correct die, while larger sizes, typically from around 25mm² or 35mm² upwards, usually need a hydraulic crimping tool. Always use a die that matches the splice size so the barrel is compressed fully, and follow the manufacturer's crimping guidance.
Can a butt splice join two different cable sizes?: A standard copper tube butt splice is designed to join two conductors of the same size. Joining different sizes requires a reducing splice or another approved method, otherwise the smaller conductor may not be gripped properly. Check the conductor sizes carefully before choosing a splice.
Do copper butt splices need to be insulated?: Yes, copper tube butt splices are bare metal, so the joint must be insulated after crimping. Heat shrink tubing is the usual choice, slid over the cable before crimping and then shrunk over the splice with overlap onto the insulation. For underground or armoured cables, use a full joint kit.
Can a crimped butt splice be hidden in a wall?: Properly crimped joints made with the correct tool and insulated are generally considered maintenance-free, which means they may be acceptable in inaccessible locations. Requirements can vary, so check current wiring regulations and the manufacturer's guidance before concealing any joint, and protect the cable appropriately.