Steel
Security Bits & Keys
Driver bits and keys for installing and removing tamper-resistant security screws.
About the Security Bits & Keys
These are the bits and keys for putting in and taking out tamper proof security screws, for maintenance crews, sign installers and anyone fixing public fittings. They come as snake-eye (eye drive) bits No. 6 to No. 14, and pin hex (post hex) L keys from 2.5 to 6mm and 3/32 to 7/32 inch, each sold singly; pin Torx bits and keys have their own pages. Choose the bit or key above; the guide below shows which screw each one fits and how to tell the drives apart.
Also called tamper proof bits, snake eye bits, spanner bits or pin hex keys.
Features
- Pin-Torx, pin-hex and snake-eye
- Bit and key formats
- Matches the security screw range
Applications
- Installing and removing snake-eye and pin hex security screws
- Maintenance on signs and public fittings
Security bits and keys: what each drive needs
A security screw has a drive that ordinary screwdrivers and bits cannot turn. Each drive needs its own matching security bit or key, so order the bit with the screws: without it you cannot fit them, or get them out again later.
- Snake-eye (eye drive): two small holes in the screw head. It takes a two-pin eye drive bit. Hobson numbers these bits 6, 8, 10, 12 and 14.
- Pin hex (post hex): a hex socket with a pin in the centre. It takes a pin hex key or bit that is bored down the middle to clear the pin; an ordinary hex key will not go in.
- Pin Torx (post Torx): a six point star with a centre pin. It takes a security Torx bit or key with a hole for the pin, in the matching T size. Those bits and keys are on their own pages, linked at the foot of this page.
- One-way: a slot shaped so a flat screwdriver drives it in but cannot undo it. No special bit is needed to fit it, and it is made not to come out.
Bit or key?
- Snake-eye bits are driver bits (Hobson calls them security socket bits), for a bit holder or driver.
- Pin hex keys are L shaped keys for turning by hand, handy to keep in a toolbox or a vehicle.
- To drive pin hex screws with a drill or driver, use a pin hex security bit (same sizes, 2.5 to 6mm and 3/32 to 7/32 inch), linked at the foot of this page.
Which security bit or key fits which screw
Every bit and key on this page, with the security screws in our range that each one fits. Select a row to open it in the selector.
From the bit and key numbers in Hobson's security screw descriptions and its eye drive screw sheet. # sizes are self-tapping screws (gauge); M sizes are metric machine screws. Each bit and key is sold singly. Tap a number to show it in the selector above.
| Size | Type | Fits these security screws in our range |
|---|---|---|
| Snake-eye (eye drive) bit | ||
| No. 6 | Snake-eye (eye drive) bit | #6 countersunk and pan self-tapping screws |
| No. 8 | Snake-eye (eye drive) bit | #8 countersunk and pan self-tapping screws; M4 countersunk and pan machine screws |
| No. 10 | Snake-eye (eye drive) bit | #10 countersunk and pan self-tapping screws; M5 countersunk machine screws |
| No. 12 | Snake-eye (eye drive) bit | M5 pan and M6 countersunk machine screws |
| No. 14 | Snake-eye (eye drive) bit | #14 countersunk and pan self-tapping screws; M6 pan machine screws |
| Pin hex (post hex) key, metric | ||
| 2.5mm | Pin hex (post hex) key, metric | #8 countersunk self-tapping screws; M4 button and countersunk machine screws |
| 3mm | Pin hex (post hex) key, metric | #10 countersunk self-tapping screws; M5 button and countersunk machine screws |
| 4mm | Pin hex (post hex) key, metric | M6 button and countersunk machine screws |
| 5mm | Pin hex (post hex) key, metric | M8 button and countersunk machine screws |
| 6mm | Pin hex (post hex) key, metric | No screw in our security screw range (for other 6mm pin hex screws) |
| Pin hex (post hex) key, imperial | ||
| 3/32 inch | Pin hex (post hex) key, imperial | No screw in our security screw range (for imperial pin hex screws of this key size) |
| 1/8 inch | Pin hex (post hex) key, imperial | No screw in our security screw range (for imperial pin hex screws of this key size) |
| 5/32 inch | Pin hex (post hex) key, imperial | No screw in our security screw range (for imperial pin hex screws of this key size) |
| 3/16 inch | Pin hex (post hex) key, imperial | No screw in our security screw range (for imperial pin hex screws of this key size) |
| 7/32 inch | Pin hex (post hex) key, imperial | No screw in our security screw range (for imperial pin hex screws of this key size) |
Pin Torx screws and the bit size each one takes
Our pin Torx security screws take these T sizes (from the screw descriptions). The pin Torx bits and keys are on their own pages, linked at the foot of this page.
- T10: #6 self-tapping screws and M3 machine screws.
- T15: #8 self-tapping screws.
- T20: #10 countersunk self-tapping screws and M4 machine screws.
- T25: #10 button head self-tapping screws and M5 machine screws.
- T27: #14 button head self-tapping screws.
- T30: #14 countersunk self-tapping screws and M6 machine screws.
- T40: M8 machine screws.
- T45: M10 and 3/8 UNC machine screws.
- T50: M12 machine screws.
Snake-eye machine screws: pan and countersunk take different bits
For the metric snake-eye machine screws the bit depends on the head as well as the size. From Hobson's eye drive screw sheet: M4 takes the No. 8 bit in both heads; M5 takes No. 10 in a countersunk head and No. 12 in a pan head; M6 takes No. 12 countersunk and No. 14 pan. The self-tapping screws take the bit with the same number as the gauge (#6 takes No. 6, and so on) in both heads.
Using security bits and keys
- Check the drive and size on the screw packet or description, and pick the bit or key from the table above.
- Seat the bit fully in the recess and keep it in line with the screw, so the pins or the screw's centre pin are not damaged.
- Drive at a steady, moderate speed and stop when the head is snug. Hobson suggests a slower installation speed for stainless screws, to avoid galling (threads locking up).
- Keep the bits and keys somewhere secure. Anyone with the matching bit can remove the screws, so control who has them.
What the bits and keys are made of
Hobson lists these bits and keys as plain finish steel, for driving its 304 stainless security screws. Keep them dry and lightly oiled so they do not rust in a toolbox or glovebox.
Security bits in Adelaide
Allmat supplies security bits, keys and tamper proof screws to builders, councils, sign makers and trade across Adelaide and South Australia. Add the bits to a quote with the screws, and we will price the lot.
Security bits and keys for tamper proof screws
Security bits and keys, with the tamper proof screws they drive, are available to order from Allmat for builders, councils, sign makers, maintenance crews and trade across Adelaide and South Australia. Order through Allmat, we pick and pack it, then click and collect from the Allmat yard or have it delivered to site.
Goes with
Questions
What bit do I need for a snake-eye screw?
A two-pin eye drive bit with the same number as the screw: No. 6 for #6, No. 8 for #8, No. 10 for #10 and No. 14 for #14 self-tapping screws. Metric screws differ by head: M4 takes No. 8; M5 No. 10 countersunk or No. 12 pan; M6 No. 12 countersunk or No. 14 pan.
What size pin hex key for an M6 security screw?
4mm for our M6 button and countersunk pin hex screws. M4 takes 2.5mm, M5 3mm and M8 5mm; #8 countersunk self-tapping screws take 2.5mm and #10 take 3mm.
Will a normal hex key or Torx bit fit a security screw?
No. Pin hex and pin Torx screws have a pin in the centre of the recess, so they need a security bit or key with a hole down the middle to clear the pin. Snake-eye screws need a two-pin eye drive bit.
Where are the security Torx bits?
On their own pages: pin Torx security bits (T10 to T50) and pin Torx keys, both linked at the foot of this page. The T size each of our pin Torx screws takes is listed in the guide above.
Are security bits sold singly?
Yes, each snake-eye bit and pin hex key on this page is sold singly. The screws are sold in packs.
How do I remove a one-way screw?
One-way screws are made not to come out: the slot gives a screwdriver nothing to grip in the undo direction. Use them only where the screw is permanent.
Where can I buy security bits in Adelaide?
Order through Allmat. Order ahead by phone on 1300 03 03 63 or send your list for a quote, then click and collect from 25 Kapara Road, Gillman, or have them delivered to site.
Security Bits & Keys: sizes and finishes we supply
15 lines by type and finish. Pick one above for its product code and pack sizes.
| Head | Finish | Sizes | Lines |
|---|---|---|---|
| Standard | Steel | No.6, No.8, No.10, No.12, No.14 | 5 |
| Hex | Steel | 2.5mm, 3mm, 4mm, 5mm, 6mm | 5 |
| Hex | Steel | 3/32, 1/8, 5/32, 3/16, 7/32 | 5 |
Data sheets and documents
The documents for the product you choose are listed with the selector above. Here is every Security Bits & Keys document from Hobson Engineering.
All Security Bits & Keys documents (4)
Data sheets and technical data (2)
Did You Know flyers (1)
Guides and articles (1)
Need them in bulk?
Add the sizes you need to your quote, or send us your list and we’ll price the lot and supply it with the rest of your order.
Browse all security screws