They are designed to fit inside the two poles thus enabling you to join 2 longer lengths together, the join must be supported by a bracket.
eBay
1set 200cm Plastic Roller Blinds Bracket Pull Cord Connector Curtain Chain Connector For Vertical Blinds Joiners Spare Tool Part
Aliexpress UK
1 x 200cm Pole. 1 x 150cm Pole. 1 x 125cm Pole. 5 Sided Bay Pole Set. Pole thickness (gauge): 1.2mm. Prices: Bay Pole Set £115.99. 7 x Passing Brackets (Wall mounting only). Nets requiring Overlocking may be delayed during busy periods.
eBay
Universal ID30-100mm Silicone Flexible Hose Air Intake Pipe Radiator Tube High Pressure Temperature Rubber Joiner Length 40-70cm
Aliexpress UK
28mm Poles in a variety of colours. All poles over 200cm are supplied in 2 peices with a Connector. Many people ask us about Bay Windows and these accessories are the easiest solution for smaller / larger bay windows that a standard bay pole kit wont fit.
eBay
50Pcs-Pack High-Pressure Hose Crimp Tools Stainless Steel Sleeve Pipe Exhaust Connector 11.5MM -18MM Pipe Joiner
Aliexpress UK
The elbows are designed to slide inside 35mm poles to fit inside an angled bay window. For 90 degree angles, use the Double Elbow Joint. Co-ordinates with the Speedy range of curtain poles. Isle of Man.
eBay
Windshield Wiper Washer Nozzle Hose With Connector Kit T Y I 3 Types Joint Windscreen Spray Jet Water Hose Fluid Tube Joiner
Aliexpress UK
Rolls Neo Joining Piece by Hallis Hudson, designed for use with the 19mm,28mm and 35mm Neo collection of curtain poles from Hallis Hudson. Used to join 2 poles together to achieve a longer length and must be supported by a bracket.
eBay
20 PCS Agriculture Spray Pipe Crimp Connector Hose Crimp Tools Sleeve Pipe Exhaust Connector 11.5MM -16MM Pipe Joiner
Aliexpress UK
A Middle Curtain Pole Bracket Will Be Required To Give Your Curtain Pole Suitable Support.
eBay
SEAMETAL 128Pcs Vacuum Connector Assortment Plastic Hose Joiner Tee Water Spray Pipe Joints Plastic Straight T Piece Connectors
Aliexpress UK
This pole joiner slots inside the two 28mm curtain poles to enable them to create an invisible join that must be supported by suitable bracket. You will need a suitable adapter to use the item in your country.
eBay
KegLand PCO38 Gen2 Black Elbow Cap Insert - Dip Tube to Carbonation Cap Joiner Home Brewing
Aliexpress UK
Single corner joint elbow bracket for 35mm curtain poles. Ideal for connecting two poles around a corner or bay window. Perfect for achieving a neat, professional curtain fit in complex window areas. Provides a smooth, continuous pole layout around corners.
eBay
VR - Alloy Aluminum Hose Adapter Joiner Pipe Connector Silicone 63mm or 70mm or 76mm color silver
Aliexpress UK