Stem Adaptor (BSP Thread)

Stem Adaptor (BSP thread) 4mm × 1⁄8″
Disclaimer: All images are for illustrative purposes only.

Quickly and easily connects two John Guest fittings to create a swivel type connection.

John Guest stem adaptor (BSP thread) push-fit fitting adapts a push-fit connection to a swivel type connection. Fast and simple to install, John Guest Air and Pneumatics creates an instant connection and airtight seal without the need for tools, hot works or sealing agents. Air piping systems can be set up and installed 50% quicker than traditional methods.

The unique collet locking design firmly and securely holds the pipe in place without deforming the pipe or restricting flow. Fittings are also fully demountable, reducing system downtime during maintenance and making it quick and easy to modify or extend systems.

Designed in tough engineered plastic, fittings are compatible with John Guest nylon, powder coated aluminium or LLDPE tubing, as well as copper, PEXa and other soft metal pipe materials. All John Guest fittings are manufactured and assembled in the UK.

Features and benefits

  • Strong acetal copolymer fitting with nitrile O-Ring
  • Airtight connection with superior flow characteristics
  • Instant push-fit connection and demountable without tools
  • Secure collet cover prevents accidental disconnection
  • Suitable for air and pneumatics piping systems up to 10 bar
  • Ideal for air, inert gases and vacuum applications
  • Food grade fitting suitable for potable liquids
  • Compatible with soft metal or plastic pipe/tubing


BSI Thermo Pipes and Fixings accredited
SKUDescriptionPipe OD mmBSP ″Quantity per bagQuantity per boxAccreditations
PM050411EStem Adaptor (BSP thread) 4mm × 1⁄8″41⁄810500
PM050412EStem Adaptor (BSP thread) 4mm × 1⁄4″41⁄410500
PM050511EStem Adaptor (BSP thread) 5mm × 1⁄8″51⁄810500
PM050512EStem Adaptor (BSP thread) 5mm × 1⁄4″51⁄410500
PM050611EStem Adaptor (BSP thread) 6mm × 1⁄8″61⁄810500
PM050612EStem Adaptor (BSP thread) 6mm × 1⁄4″61⁄410500
PM050811EStem Adaptor (BSP thread) 8mm × 1⁄8″81⁄810500
PM050812EStem Adaptor (BSP thread) 8mm × 1⁄4″81⁄410300
PM050813EStem Adaptor (BSP thread) 8mm × 3⁄8″83⁄810300
PM051012EStem Adaptor (BSP thread) 10mm × 1⁄4″101⁄410300
PM051013EStem Adaptor (BSP thread) 10mm × 3⁄8″103⁄810200
PM051014EStem Adaptor (BSP thread) 10mm × 1⁄2″101⁄210200