Caplugs 99390513 Plastic Rectangular Finishing Cap with Flat End Grip. VRF-090X1000-16, VINYL, Length 1.000" ID 1.000", Black (Pack of 80) : Amazon.co.uk: Business, Industry & Science
4pcs Rectangle Ribbed Plastic Insert Plugs End Caps Rectangular tubing end Cap : Amazon.co.uk: DIY & Tools