Align the hole plug to the hole and press it, the installation is complete.
eBay
1-30pcs Square Pipe Plug Plastic Black Blanking End Cap Tube Pipe Insert Plug Bung 20x20 25x25 30x30 40x40 mm
Aliexpress UK
Rubber stopper/Silicone Cap/rubber hole plug. -Material: Silica gel/Food grade silicone. -Shape: Round cap shape.
eBay
Black Square Plastic Black Blanking End Cap Pipe Plug Foot Furniture Inner Plug Cover 10x10mm ~ 100x100mm
Aliexpress UK
Such as iron plate, stainless steel, furniture panel, plug the excess holes to keep the panel beautiful. Colour:Black White Yellow Grey Red Brown Brown. Snap nylon plug, pressure-resistant, wear-resistant, non-toxic, odorless, easy to install,Suitable for a variety of flat holes.
eBay
Black / White Snap-on Plug 5 6 8 9 10 11 12 13 14mm to 50mm Plastic Hole Plug Blanking End Caps Tube Pipe Inserts Plug Bung
Aliexpress UK
Round Solid Silicone Rubber Seal Hole Plugs Blanking End Caps Seal Bung 3mm-15mm.
eBay
Silicone Rubber Conical Snap-on Blanking End T-type Plug Hole Plug Caps Seal Stopper Pipe Tube Inserts Dust Bung 2.5-50.6mm
Aliexpress UK
Product Features: Corrosion Resistance, Acid and Alkali Resistance, High Temperature Resistance, Uv Resistance, Aging Resistance, Long Service Life, High and Low Temperature Resistance, Etc. P ackage includes:1x Hole Plug End Cap.
eBay
8mm To 38mm Alloy Aluminium Dump blow off valve Bov Blanking Plug Silicone Hose Blanking Plug
Aliexpress UK
Say goodbye to unsightly holes and hello to a professional finish. Clean and Professional Finish : With a wide range of hole sizes available, our hole plugs provide a clean and professional finish, effectively concealing unsightly holes in your panels and flat surfaces, enhancing the overall aesthetics of your projects.
eBay
Size 8mm-32mm Alloy Aluminium Plug blow off valve Bov Blanking Plug Silicone Hose Blanking Plug 8 10 12 14 16 18 20 22 28 30 32
Aliexpress UK
Size：5mm 6mm 7mm 7.5mm 8mm 9mm 10mm 11mm 12mm 13mm 14mm 15mm 16mm 17mm 18mm 19mm 20mm 22mm 25mm 28mm 30mm 32mm 35mm 38mm 40mm 42mm 45mm 48mm 50mm 55mm 60mm. Colour：Default Black(The colors include black, white, gray, yellow, coffee, brown, dark gray, beige, reddish brown, blue, etc. ).
eBay
Alloy Aluminium 10/12/14/16/18/20/22/25/34/38 Mm Dump Blow Off Valve Bov Blanking Plug Silicone Hose Blanking Plug
Aliexpress UK
Suitable for sealing various holes such as screw holes, circular holes, square holes, etc. Buckle design, easy to install and disassemble. （4） Fixed function: By clamping the edge of the hole with a clip, it ensures a secure fixation.
eBay
10-50pc PVCrubber end cap, screw end cap, plastic tube, hub thread protector, push in cap, rubber cap, rubber threaded cap
Aliexpress UK