They Will Suit Either Countersunk Pozi Star Head Wood Screws or Self Tapping Screws. The 99p option is for a sample random colour cap .
eBay
Allen Key Hexagon Socket Head Bolts Cap Screws Stainless Steel Long M3 M4 M5 M6 M8 Extra Long 4mm To 300mm
Aliexpress UK
Quantity: 160pcs. Size: M4 M5 M6 M8 M10 M12. Type: Bolt Covers. Material: Plastic.
eBay
M8*15mm Square Taper Bottom Bracket Bolts Titanium Alloy CNC-machined BB Fixing Screws W/Cap Gasket MTB Road Bike Ti Parts
Aliexpress UK
M12 nut cap (19mm key). M5 nut cap (8mm key). M6 nut cap (10mm key). M8 nut cap (13mm key). M10 nut cap (17mm key). Protection against outdoor weather. Material: plastic.
eBay
SMLLOW Bike Parts MTB Road Bike Crank Arm Bolt For Bottom Bracket Cap M18/M19/M20*10 Crankset Screw For Parts Bicycle BB Axis Sc
Aliexpress UK
Beautify and protect the screws. Plastic snap screw cover, durable, anti-aging, waterproof and smooth on surfaces. Suitable for 3.5-4.0mm flat head variety length specifications tapping screws. Colour: Black, White, Light Gray, Dark Grey.
eBay
10pcs Rubber Material Waterproof M6 Screw Dustproof Outdoor MTB Bike Bicycle Headset Cap Bolts Parts Stem Top Cover
Aliexpress UK
Designed To Fit Over An 8mm Hex Head Screw With An EPDM Washer. KW1-KW17, PA20-PA38, PA41-PA49, PA60-PA78, PH4-PH44, PH49-PH50, PO (Isle Of Wight) TR (Isles Of Scilly) ZE (Channel Isles). Perfect Way To Blend In Roofing And Construction Screws With Coloured Panels.
eBay
ZTTO Bicycle Crank Arm Bolt Aluminum Alloy Crank Screw Caps MTB Road Bike Crank Cover Screws M20 M19 M18 Universal For M6000 105
Aliexpress UK
To protect and cover bolt head or nut. grey colour finish. made from polyethylene plastic (LDPE). for a proffesional finished look.
eBay
Hex Socket Screw Kit DIN912 Black Grade 12.9 Carbon Steel Hexagon Round Cap Allen Bolt Nut Washer M2 M3 M4 M5 M6 Machine Screws
Aliexpress UK
Plastic, fold over, hinged type. Available in Black, White & Yellow.
eBay
TOOPRE Bike Crankset End Cap Bolt Extractor For FSA Crank Screw Removal Tool Bicycle Chainring Crank Screw Removal Tool
Aliexpress UK
Suitable for Countersunk screws. ALL PRODUCTS MATT FINISH FOR 10-12 Gauge screws. - Furniture upholstery. - A plastic washer (base), through which he screw is inserted. - A plastic cap, which locks over the washers, providing an air & watertight seal that protects fastener head from rust and corrosion.
eBay
Bicycle Compression Plug Steerer Headset Expansion Bolts Insert Bowl Top Cap Mount 1 1/8" Expander Nuts Carbon Fork Anchor
Aliexpress UK