Security Fasteners

Security Fastener Selection — Quick Reference (Tamper-Resistant Profiles)

Security fasteners have tamper-resistant drive geometries that prevent removal with standard tools — used on AU public infrastructure, electrical equipment, vehicles, retail fixtures, building services where unauthorised access is a real risk.

Critical: Security fasteners are "security" by REQUIRING SPECIAL TOOLS to remove — not unremovable. Always keep matched removal tools available for authorised maintenance. Champion OWS-RT is the standard one-way screw removal tool when authorised removal is needed. Compliance: Public infrastructure + electrical isolation often specifies particular drive types (e.g. snake-eye for utility access). Brand: Champion. Companion: all fasteners, one-way screws, extraction & removal tools.

Security Fasteners for Australian Public Infrastructure and Tamper-Resistant Installations

Security fasteners are the screws, bolts, and nuts with tamper-resistant geometries that prevent removal with standard tools. Used widely on Australian public infrastructure, electrical equipment, vehicles, and building services where unauthorised access is a concern, security fasteners are the first line of defence against vandalism, theft, and tampering. AIMS Industrial supplies security fasteners across the established tamper-resistant profiles.

The security fastener types we stock

• Torx security screws (pin-in-Torx) — standard Torx head with a central pin; the most common modern security fastener
• Pin-hex security screws — Allen socket with a central pin requiring matching pin-hex driver
• One-way (clutch head) screws — slot drives that turn one way only; standard slotted driver tightens but cannot loosen
• Snake-eye (two-pin) screws — two-pin drive requiring matching snake-eye driver
• Tri-wing screws — three-wing drive used in some electronics and consumer products
• Spanner-drive (pin-spanner) screws — two holes in the head requiring matching pin-spanner driver
• Sentinel head bolts — bolt heads with smooth domed tops that can't be gripped by standard wrenches
• Shear-off (snap-off) bolts — designed to break off at a calibrated torque, leaving an undriveable head
• Security nuts (one-way) — see also security nuts and clips

Where security fasteners earn their place

• Public infrastructure — bus shelters, street signs, signage, lighting columns, public seating
• Electrical equipment — distribution boards, sub-mains, access covers in public areas
• Schools and public buildings — fittings exposed to vandalism risk
• Vehicles and rolling stock — number plate fastenings, exterior fittings, security-sensitive components
• Vending and dispensing machines — internal access fastenings
• Building services — service panel covers, lift access panels, lockable utility access

Materials and finishes

• Steel zinc-plated — the everyday choice for protected and indoor applications
• Stainless steel 304 and 316 — for outdoor and corrosive environments where coating durability matters
• Hot-dip galvanised — for heavy-duty outdoor applications requiring thicker zinc protection

Sizing — match to load and substrate

Security fasteners come in metric and imperial thread sizes matching standard fasteners. Common sizes range from M4 through M16 for screws, with bolt sizes through M24 and beyond for structural applications. Match the security fastener size to the load and substrate as you would for a standard fastener; the security feature is in the head geometry, not the load-bearing function.

The matching driver — essential

Security fasteners are only as effective as the rarity of the matching driver. For premium security applications, choose the less common security profiles (snake-eye, tri-wing) rather than the widely-available Torx security. For routine service-restricted applications, Torx security with a pin is standard and convenient. Drivers and bits for security fasteners are stocked in our security bits range.

Brands stocked at AIMS

Hobson and Bremick cover the security fastener range across the standard sizes, materials, and finishes. For specialty security profiles or specific applications, we source through our distribution channels.

Companion ranges at AIMS

Security fasteners sit alongside our broader fastener range — see security screws, security nuts and clips, security bits, and socket countersunk screws for the related products.

Need help speccing security fasteners for a specific application or compliance requirement? contact our team — we'll match by application, substrate, and security level.

People Also Ask — Security Fasteners (Tamper-Resistant)

Q: What are security fasteners?

Security fasteners (also called tamper-resistant fasteners or anti-theft fasteners) use specialised drive types that prevent easy removal by standard tools. Common types: pin-Torx (Torx with central pin), spanner head (two-hole drive), one-way (slot screws that drive in but not out), security Torx, snake-eye drive, breakaway head bolts (snap off when tightened). Used in: public infrastructure (street furniture), retail security (display fixtures), licence plates and registration, vehicle anti-theft, and industrial security applications.

Q: What drive types are most common?

Pin-Torx (Torx with central pin): most common security drive, requires specialty pin-Torx bits. T10, T15, T20, T25, T27, T30, T40 common sizes. Snake-eye (two-hole spanner head): less common, requires snake-eye bit. Square head (Robertson): not strictly security but harder to remove without correct bit. One-way drive: rounded ramps allow tightening but slip on loosening. For each drive type, specialty bits required — workshop kits include security bit assortments for common drives.

Q: How do I install security fasteners?

Standard installation — drill or tap the receiving hole, apply security fastener with the appropriate security bit. For breakaway-head bolts: tighten until head snaps off at the design break point (no further removal possible). For pin-Torx and similar: drive to required torque, the bit can be left for installer use. For permanent installations, also apply thread-locker (Loctite 263 red) to prevent any rotation. The combination of unusual drive + threadlocker provides maximum security.

Q: Are security fasteners actually unbreakable?

No — determined attack with appropriate tools (drilling, cutting, grinding) defeats any fastener. Security fasteners deter casual or opportunistic theft (people without specialty tools) and slow professional attack. They're one layer in a security strategy — combine with physical barriers, surveillance, and access control. For high-security applications (vault doors, ATM internals), specialty engineered security fasteners with additional features. For street furniture and retail: standard security fasteners are adequate.

Q: What bits do I need for security fasteners?

Pin-Torx bits (T10-T40 typical workshop range), snake-eye bits (size to match fastener), one-way bits (rarely used for removal — installation slots in only), specialty drives per application. Quality pin-Torx bits: Wera, Wiha, Bondhus. AIMS stocks security bit sets covering common drives. For specialty industrial applications, match the bit precisely to the fastener — using wrong bit damages the fastener head and the bit.

Q: What is a Sentinel head bolt?

Sentinel head bolts have a smooth, domed bolt head with no flats, edges or drive features that a standard wrench or socket can grip. Removal requires a specialist Sentinel-head socket, making them effective for tamper-resistant structural and infrastructure fastening where the bolt head itself — not just a screw drive — needs to resist unauthorised removal.

Q: Which security fastener finish should I use outdoors?

For outdoor and corrosive environments, use stainless steel 304 or 316 security fasteners rather than zinc-plated — the coating on zinc-plated fasteners degrades faster outdoors and compromises long-term corrosion resistance. For heavy-duty outdoor structural applications needing thicker zinc protection, hot-dip galvanised is the alternative. Zinc-plated remains the standard choice for protected indoor applications.

Q: How do I remove a one-way security screw when authorised?

One-way (clutch head) screws drive in with a standard slotted driver but are designed so a standard driver cannot back them out. For authorised removal, use the Champion OWS-RT removal tool — a specialist one-way socket gripper. As a last resort where the removal tool isn't available, drilling out the screw with a one-way removal drill bit will force removal, destroying the fastener in the process.

Q: Why choose a snake-eye or tri-wing drive over standard Torx security?

Torx security (pin-in-Torx) is the most common security drive, and matching drivers are relatively easy to obtain — making it convenient for routine, service-restricted applications but less effective where genuine tamper resistance matters. For premium security applications, choose a less common profile such as snake-eye (two-pin) or tri-wing, since the security value of any tamper-resistant fastener depends on how rare the matching driver is.