Leading Suppliers Nationally for Valves, Switching, Solar Operated Systems, Piezoelectric Technology

Sure, here is a list of leading companies in the United Kingdom for the specified industries in Markdown format:

Valves:

1. AVK
2. Spirax Sarco
3. IMI plc
4. Crane Co.
5. Rotork

Switching:

1. Honeywell
2. Schneider Electric
3. Siemens
4. ABB
5. Eaton

Solar Operated Systems:

1. Solarcentury
2. Lightsource BP
3. Octopus Energy
4. EvoEnergy
5. SolarEdge

Piezoelectric Technology:

1. Morgan Advanced Materials
2. PI Ceramic
3. CeramTec
4. APC International
5. Mad City Labs

These companies are among the key players in their respective industries in the United Kingdom.