About ISG
The Interconnect Solutions Group is a specialist distributor of wire, cable, connectors and harness components. Three decades of working with the most demanding industries in the world means we understand what they need — and what goes wrong when they don't get it.
Our Story
The Interconnect Solutions Group was formed to bring together specialist interconnect businesses across the UK, USA and Europe. Each company has its own identity, its own market and its own customer relationships — what they share is a commitment to technical depth and doing the job properly.
We are not a generalist distributor. Every company in the ISG group has been built around deep expertise in specific interconnect product areas and the industries that depend on them. Our people understand the difference between a specification-compliant component and one that will simply fit — and that knowledge protects our customers' projects.
From aerospace and defence harnesses assembled under traceability-controlled conditions, to rapid race-day connector supply for Formula 1 — ISG businesses operate wherever precision and reliability cannot be compromised.
The Interconnect Solutions Group is a division of Diploma PLC, a FTSE 100 company. Diploma builds and supports specialist distribution businesses in markets where technical knowledge and reliable supply genuinely matter — interconnect is a natural fit for that model.
Our group spans the UK, USA, Germany and Czech Republic, with distribution networks extending across France, India, China, Turkey and Poland. This geographic breadth gives ISG customers access to global sourcing, local expertise and rapid supply capability across multiple time zones.
The businesses that form ISG have collectively built up over 35 years of interconnect expertise. We've supplied the world's most demanding industries through significant shifts in technology and manufacturing practice — and the product range, supplier relationships and technical knowledge that came from that are what we operate with today.
Our History
1987
Rayfast Founded
Rayfast established in the UK as a specialist distributor for Raychem, building deep expertise in heat shrink tubing for aerospace and defence.
1994
Diploma PLC Acquires Rayfast
Diploma PLC enters the interconnect sector with the acquisition of Rayfast, providing long-term financial backing for group growth.
1998
Sommer GmbH Acquired
Sommer in Germany acquired, establishing a major European footprint and adding precision cable and connector assembly expertise.
1999
IS Group Rebranded
Introduction of the IS-Group identity — businesses renamed and rebranded under a unified group identity to reflect shared values and capabilities.
2001
Rayfast USA Established
North American operation launched, entering the US defence, aerospace and industrial markets with dedicated US-held stockholding.
2007
Cabletec Acquired
Cabletec joins the group, adding braided sleeving and deep cable expertise to serve the UK industrial, marine and rail sectors.
2012
Rayquick into Sommer
Rayquick GmbH acquired in Germany and fully integrated into Sommer, further expanding the group's European cable and assembly capability.
2017
Krempfast Integrated
Krempfast Ltd acquired and integrated into the ISG-UK operation, supporting growth into emerging interconnect markets.
2020
HSP into Sommer
HSP acquired in Germany and integrated into Sommer GmbH, further strengthening the group's precision assembly and European customer base.
2021
Brand Refresh
Group-wide brand refresh to modernise the ISG identity and demonstrate cohesion and shared purpose across all nine businesses.
2022
LJR Electronics Acquired
LJR Electronics, based in Miamisburg, Ohio, acquired — significantly strengthening ISG's North American connector capability.
2023
Filcon & CTS Acquired
Filcon Electronic (Germany) integrated into the group; CTS acquired and integrated into Sommer, deepening European connector and assembly capability.
2025
Rayfast s.r.o. & Astro Industries
Rayfast s.r.o. officially launched in Prague; Astro Industries Inc acquired in Dayton, Ohio — adding motorsport interconnect expertise to the group.
2025
Selwyn Electronics Acquired
Selwyn Electronics, a UK connector and cable assembly specialist founded in 1984, joins the Interconnect Solutions Group — bringing over 40 years of interconnect expertise and expanding ISG's connector offering.
Today
ISG — A Unified Group
Nine specialist businesses. Multiple locations worldwide. Nearly 40 years of interconnect expertise serving the world's most demanding industries.
Our Companies
Rayfast UK
United Kingdom
The founding business of the ISG group. UK-based specialist in heat shrink tubing, wire and cable for aerospace, defence and industrial markets. Holds significant UK stock with same-day despatch capability.
Rayfast USA
United States
North American arm of Rayfast, supplying US defence, aerospace and industrial markets with specialist interconnect from strategically located US stockholding. Dual-source capability for transatlantic programmes.
Rayfast s.r.o.
Czech Republic
Central European distribution operation serving German, Czech and broader European markets with the Rayfast product range, providing local language support and EU-held stock for rapid continental supply.
Sommer GmbH
Germany
German specialist in precision cables and connector assemblies for demanding industrial, medical and automotive applications. Deep technical engineering capability and strong relationships with European OEM customers.
LJR Electronics
United States
US connector specialist based in Miamisburg, Ohio, with broad stock coverage across circular, rectangular and PCB-mount connector families. Technical expertise in MIL-SPEC and COTS connector selection for defence and industrial programmes.
Cabletec
United Kingdom
UK-based cable and wire specialist serving a broad range of industrial, marine and rail customers. Known for deep stock, fast response and technical knowledge of cable constructions and environmental ratings.
Astro Industries
United States
Specialist in motorsport and high-performance automotive interconnect. Supplying Formula 1, WEC and IndyCar teams with ultra-lightweight wire, sealed connectors and fire-protection sleeving under race-day lead times.
Filcon Electronic
Europe
European connector specialist with deep expertise in precision connectors for demanding industrial and aerospace applications. Extends ISG's connector capability and geographic reach across European markets.
Selwyn Electronics
United Kingdom
UK-based specialist in connectors, assemblies and interconnect solutions. ISG's newest member, bringing additional connector expertise and established customer relationships to the group.
What We Stand For
We do not compromise on specification. Every product we recommend, stock and supply is selected because it is the right solution — not the easiest one. Our customers trust us with programmes where full traceability, qualification documentation and specification compliance are non-negotiable.
Same-day despatch is not a headline — it is our baseline expectation. We hold significant stock and we move fast, because we understand that project delays cost our customers money and reputation.
ISG is built on relationships. Our specialists know their customers, their applications and their projects. When you call us, you speak to someone who understands the problem — and has the knowledge to help solve it.