They are tightened and loosened with an allen/ hex key drive. Available Material: High Tensile – 10.9 Grade. 6BA, 4BA, 2BA Countersunk, Hex or Allen Socket Screw/ Bolt, 10.9 High Tensile Steel, BS2470.
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5pcs Watch Case Back Cover Screws for G-SHOCK for Casio GA-110/120/150 DW6900/5600 Stainless Steel Bottom Screw Watch Tools
Aliexpress UK
With a slotted countersunk head.
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2-50pcs Cross Countersunk Screws M2 M2.5 M3 M4 M5 M6 M8 Phillip Flat Head screw Solids pan head Copper Machine Brass Bolt
Aliexpress UK
2BA x 1 1/2" Socket Cap Head Screws. A2 Stainless Steel.
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20-200pcs Black Carbon Steel Phillips Truss Head Screws M2.3 M2.6 M3 M3.5 M4 M5 M6 Cross Flat Head Self-Tapping Screws
Aliexpress UK
Loads more being listed so take a look if you need different sizes.
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NINDEJIN 10-100pcs Round Button Head Hex Self Tapping Screw M2 M2.5 M3 M3.5 M4 M5 M6 Carbon Steel Allen Hex Socket Wood Screws
Aliexpress UK
(10pk) 9BA x 2" long Steel Cheese head Screws. Machine Turned. Ideal For Model Engineering. Other 2" long screws available.
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5.5mm Watch Crown Screw Pusher Fit For Daytn Watch Case 116500 116520 Watch Crown Pusher Contains Crown tube Screw key Parts
Aliexpress UK
Each screw has a 1BA thread and they are 11/16in long. These are sold in sets of 2 or 4 screws.
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10pcs ISO7380 Allen socket Screw M3 M4 M5 M6 Colourful Aluminum Alloy Hex Hexagon Socket Round Button Head Machine Screw Bolts
Aliexpress UK
Raised Countersunk Slot Machine Screws. Emfast supplies a wide range of fasteners and fittings to the automotive, aerospace, defence, engineering, and motorsport sectors. Stainless Steel Grade A2 304.
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8pcs R/C Drone Quadcopter Brushless Motor Mounting Screws Propellers Props Fixing Screws Spare Parts
Aliexpress UK
Loads more being listed so take a look if you need different sizes.
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Watch Screw Tube Rod Spring Bar for Leather Watchband Screw-In Watch Lug Stem Link Kit 14 16 18 20 22mm Bracelet Repair Tools
Aliexpress UK