Equal compression
Join two pipe ends with the same outside diameter. Both ends are compression connections.
Description
Make the right connection between pipe runs
Extend an MDPE run, join different pipe diameters or connect pipe to a threaded component. This range brings equal couplings, reducers and BSP adapters together so you can choose the fitting for the two ends you need to join.
Start with the pipe’s outside diameter, then check the other end: another pipe size, or a male or female BSP thread. The selector above lists the exact combinations.
Four ways to connect
Identify what goes into each end before selecting your fitting. Photographs show connection styles.
Reducing compression
Join two different pipe sizes. This range includes 25mm–20mm, 32mm–20mm and 32mm–25mm.
BSP male adapter
Connect MDPE pipe to a matching female BSP fitting. The separate black threaded end is the BSP connection.
BSP female adapter
Connect MDPE pipe to a matching male BSP fitting. Check the nominal thread size as well as the pipe size.
Find your size combination
Not every pipe diameter is offered with every thread size.
Pipe to pipe
Equal couplings: 20mm, 25mm, 32mm, 40mm or 50mm at both ends.
Reducing couplings: 25mm–20mm, 32mm–20mm or 32mm–25mm.
Pipe to BSP thread
- 20mm pipe: ½-inch or ¾-inch male/female; 1-inch female.
- 25mm pipe: ½-inch, ¾-inch or 1-inch male/female.
- 32mm pipe: ¾-inch or 1-inch male/female.
- 40mm pipe: 1-inch male.
- 50mm pipe: 1½-inch or 2-inch male.
BSP sizes are nominal thread sizes, not direct inch measurements of the opening. Use the “What is BSP?” guide in the product information if you need help identifying a thread. The grey nuts belong to the pipe compression connections.
Prepare the joint before assembly
Plan enough access to assemble the fitting and support the adjoining pipework.
Prepare the pipe ends
Isolate and depressurise the supply. Cut sound pipe square, clean the ends and follow the fitting guidance for insertion depth, assembly and any required pipe liner.
Match threaded parts
For BSP adapters, match the nominal size and opposite thread gender. Align the joint squarely and use a suitable sealing method; avoid cross-threading or overtightening the plastic body.
Support and inspect
Support the pipe and connected components. Restore the supply gradually and inspect the joints. Check the complete system’s suitability for its service conditions rather than relying on the PN10 designation alone.
Before you order
Which measurement do I use for the pipe?
Measure across the outside of the MDPE pipe. For an equal coupling, both pipes must match the selected size. For a reducer, each pipe must match its corresponding end.
Do I receive every fitting shown?
No. Each order quantity supplies one fitting in the selected size and connection type. Pipe, clips, mating fittings, separate seals and pipe liners are not included.
Product information & technical details
| SKU | MDPESTR20001[#ML] |
|---|---|
| Product type | |
| BSP thread size | 1/2", 3/4", 1", 1.5", 2" |
| Thread gender | Male, Female |
| MDPE size | 20mm, 25mm, 32mm, 40mm, 50mm |
| Colour | Black, Grey |
|---|---|
| Material | Plastic |
| Connection styles | Equal compression, reducing compression, compression to BSP male, or compression to BSP female; depends on selected option. |
| Pressure designation | PN10. Suitability depends on the complete assembly and service conditions. |
| Pack contents | One straight fitting in the selected size and connection type. Pipe and installation accessories are not included. |
What is BSP?
What is BSP thread size?
BSP (British Standard Pipe) is a nominal pipe-thread size, not a direct measurement of a fitting’s bore or outside diameter. For example, a ½-inch BSP male thread measures about 21mm across its outer thread crests.
These figures are approximate outside diameters of male BSP threads, to help identify the nominal size. They are not inch-to-millimetre unit conversions:
- 3/8" BSP → 16.66 mm
- 1/2" BSP → 20.95 mm
- 3/4" BSP → 26.44 mm
- 1" BSP → 33.25 mm
- 1.25" BSP → 41.91 mm
- 1.5" BSP → 47.80 mm
- 2" BSP → 59.61 mm
- 3" BSP → 87.88 mm
- 4" BSP → 113.03 mm
Measure across the outside of a male thread, then check its pitch and whether it is parallel or tapered. Diameter alone does not confirm compatibility. Check the product’s stated thread specification before connecting.
All delivery times are estimates and not guaranteed. Orders placed before 1 pm, Monday to Friday (excluding bank holidays), will be dispatched the same day, while orders placed after 1 pm will be dispatched by the end of the next working day.
If an invalid postcode or address is provided, the order will be cancelled without further notice, as we are unable to modify addresses or print labels for invalid postcodes.
Our standard delivery option is Royal Mail Tracked 48, which typically takes 3–5 business days. If you need your order more quickly, Expedited delivery via Royal Mail Tracked 24 is available, offering a 1–2 business day service.
Large or bulky items may be sent via courier at our discretion and are usually dispatched for next-day delivery. Please note that we only ship to mainland UK addresses; delivery to non-mainland locations, including the Highlands & Islands, may not be available for large or heavy items. If your address falls into one of these areas and you wish to purchase such items, please contact us with your postcode and order details before placing your order. If we cannot ship to you, you are welcome to arrange your own courier for collection.
All products, unless otherwise stated, come with a standard manufacturer warranty against faulty workmanship.
If your product fails within six months of delivery, please contact us with your order reference number, a description of the issue, and clear images illustrating the fault.
Should your item require a return for further investigation, it is your responsibility to arrange and cover postage back to us.
If we are unable to repair the fault, we may offer either a replacement or a full refund.
In cases where the item is inspected and found not to be faulty—or where damage is determined not to be due to manufacturing defects—you will not be entitled to a refund or replacement. We will then either return the item to you via standard post or dispose of it at your request.
You may return any order within 14 days of delivery. As soon as you receive your items, please inspect them carefully—taking reasonable care to keep both the product and its packaging clean and undamaged. If you discover an error or defect after 14 days, we reserve the right to decline your return. If your product fails or breaks after this 14-day time window then your order may be eligible for a warranty claim, please see our warranty information for more details.
To initiate a return, please contact us via our contact form to obtain a return authorisation and the correct returns address (different from the address on your invoice). This can also be done through your 'recent orders' page on your account if you are registered with Shop. Returns sent without prior authorisation will be discarded.
Returned items must be in the same condition in which you received them—unworn or unused, with tags attached and in their original packaging. You must include either a copy of your invoice or a slip with your order reference number inside the parcel. Please be sure not to obscure your return reference number on the label.
If you refuse delivery or reject the parcel without prior notice, we will inspect the returned package and issue a refund upon receipt. Although there is no restocking fee, we will deduct the cost of the return postage label (£3.35) from your refund.
If the returned item or its packaging shows signs of use, damage, or staining, we may deduct up to 50% of the order value—or refuse the return entirely—depending on its condition. Examples include damaged tags, stained, modified or damaged packaging, or missing components.
For faulty, incorrect, or damaged items, please contact us before sending anything back so we can attempt to resolve the issue directly. If we agree that a return is necessary due to our error, we will provide you with a pre-paid return label.
Products that have been modified or damaged through customer action are not eligible for return. This includes, but is not limited to, items that have been cut, trimmed or otherwise altered—such as a tarpaulin or pond liner resized to your specifications—or any product showing damage beyond normal inspection handling.
All delivery times are estimates and not guaranteed. Orders placed before 1 pm, Monday to Friday (excluding bank holidays), will be dispatched the same day, while orders placed after 1 pm will be dispatched by the end of the next working day.
If an invalid postcode or address is provided, the order will be cancelled without further notice, as we are unable to modify addresses or print labels for invalid postcodes.
Our standard delivery option is Royal Mail Tracked 48, which typically takes 3–5 business days. If you need your order more quickly, Expedited delivery via Royal Mail Tracked 24 is available, offering a 1–2 business day service.
Large or bulky items may be sent via courier at our discretion and are usually dispatched for next-day delivery. Please note that we only ship to mainland UK addresses; delivery to non-mainland locations, including the Highlands & Islands, may not be available for large or heavy items. If your address falls into one of these areas and you wish to purchase such items, please contact us with your postcode and order details before placing your order. If we cannot ship to you, you are welcome to arrange your own courier for collection.
All products, unless otherwise stated, come with a standard manufacturer warranty against faulty workmanship.
If your product fails within six months of delivery, please contact us with your order reference number, a description of the issue, and clear images illustrating the fault.
Should your item require a return for further investigation, it is your responsibility to arrange and cover postage back to us.
If we are unable to repair the fault, we may offer either a replacement or a full refund.
In cases where the item is inspected and found not to be faulty—or where damage is determined not to be due to manufacturing defects—you will not be entitled to a refund or replacement. We will then either return the item to you via standard post or dispose of it at your request.
You may return any order within 14 days of delivery. As soon as you receive your items, please inspect them carefully—taking reasonable care to keep both the product and its packaging clean and undamaged. If you discover an error or defect after 14 days, we reserve the right to decline your return. If your product fails or breaks after this 14-day time window then your order may be eligible for a warranty claim, please see our warranty information for more details.
To initiate a return, please contact us via our contact form to obtain a return authorisation and the correct returns address (different from the address on your invoice). This can also be done through your 'recent orders' page on your account if you are registered with Shop. Returns sent without prior authorisation will be discarded.
Returned items must be in the same condition in which you received them—unworn or unused, with tags attached and in their original packaging. You must include either a copy of your invoice or a slip with your order reference number inside the parcel. Please be sure not to obscure your return reference number on the label.
If you refuse delivery or reject the parcel without prior notice, we will inspect the returned package and issue a refund upon receipt. Although there is no restocking fee, we will deduct the cost of the return postage label (£3.35) from your refund.
If the returned item or its packaging shows signs of use, damage, or staining, we may deduct up to 50% of the order value—or refuse the return entirely—depending on its condition. Examples include damaged tags, stained, modified or damaged packaging, or missing components.
For faulty, incorrect, or damaged items, please contact us before sending anything back so we can attempt to resolve the issue directly. If we agree that a return is necessary due to our error, we will provide you with a pre-paid return label.
Products that have been modified or damaged through customer action are not eligible for return. This includes, but is not limited to, items that have been cut, trimmed or otherwise altered—such as a tarpaulin or pond liner resized to your specifications—or any product showing damage beyond normal inspection handling.