Buy Circlips Online in Australia
Circlips & Retaining Rings
Circlips (retaining rings) are sprung metal rings that seat into a groove machined into a shaft or bore, retaining components in their axial position. They replace more complex retention methods — shoulder plates, threaded collars and pin assemblies — with a single, simple component that installs and removes with circlip pliers. Circlips are used extensively throughout machinery, automotive and industrial equipment manufacturing and maintenance. AIMS Industrial supplies circlips and retaining rings in metric and imperial sizes, external and internal, for maintenance and engineering applications across Australia. If you're weighing up which one to choose, our Circlip Guide: Types, Sizes & Installation is a good place to start.
Types of Circlips
- External circlips (shaft circlips): Seat in a groove on a shaft's outside diameter and compress to install, retaining components such as bearings, pulleys or collars on the shaft.
- Internal circlips (bore circlips): Seat in a groove inside a bore or housing and spread to install — commonly used to retain bearings within housings.
- Spiral retaining rings: Coiled spring wire rather than a stamped ring, installed without pliers — see the FAQ below for when to use one.
- Bowed circlips: A flat circlip with a slight bow for controlled axial preload — see the FAQ below.
- E-clips (DIN 6799): Small open-C-shaped retainers that slide sideways onto a shaft groove without needing pliers.
Installation & Care
Always use circlip pliers with the correct tip style (straight or angled) and tip diameter for the ring's tang holes. Forcing a circlip with the wrong pliers causes the ring to spring off unpredictably or distorts it beyond its elastic limit, compromising retention. Never reuse a circlip that has been overstressed or deformed — fit a new ring.
Circlip Installation Quick Reference — Pliers & Tool Selection
Each circlip type needs its matching pliers — check the plier's working size range against your circlip size before ordering, and make sure the nose tips seat fully into the ring's tang holes.
| Circlip Type | Pliers Required | Working Size Range (Common) | Plier Action |
|---|---|---|---|
| External / Shaft (DIN 471) | External Circlip Pliers | 3-25 mm (small), 19-60 mm (medium), 40-100 mm (large) | Squeeze handles — pliers OPEN to spread ring over shaft |
| Internal / Bore (DIN 472) | Internal Circlip Pliers | 8-25 mm (small), 19-60 mm (medium), 40-100 mm (large) | Squeeze handles — pliers CLOSE to compress ring out of bore |
| E-Clip (DIN 6799) | E-Clip Tool or Flat-Blade Screwdriver | 1.2-24 mm | Slide axially — does not require dedicated circlip pliers |
| Convertible (Internal + External) | Convertible Circlip Pliers | 10-50 mm typical | Reverse jaws to switch between internal and external use |
| Bent-Nose / Right Angle | Bent-Nose Circlip Pliers | Any size matching plier capacity | For circlips in recessed grooves where straight access blocked |
For dedicated circlip pliers, see circlip pliers. For the full ring range across DIN 471, DIN 472 and DIN 6799, see retaining rings, or read our circlip guide for background.
Order Circlips from AIMS Industrial
AIMS Industrial stocks external and internal circlips in metric and imperial sizes, in carbon steel and stainless steel. Bearing installations frequently use circlips — see bearings for the mating range. For unusual sizes or large quantities, contact our team.
Circlip & Retaining Ring FAQ
What is a circlip?
A circlip is a semi-flexible metal ring that seats into a machined groove on a shaft or inside a bore, acting as a removable shoulder to locate bearings, gears or other shaft components. Also called retaining rings or snap rings — see below for how the terms relate. AIMS stocks external (shaft) and internal (bore) circlips in metric and imperial sizes.
What is the difference between internal and external circlips?
External circlips fit around a shaft and seat into a groove on the outside — they compress to install. Internal circlips fit inside a bore and seat into a groove on the inside — they spread to install. The two types are not interchangeable and need matching pliers (see the tool reference table above) for installation and removal.
What are circlips made of — carbon steel or stainless?
Standard circlips are carbon spring steel — hardened and tempered, with a phosphate or bright finish — for the elasticity needed to repeatedly install and remove without taking a set. Stainless steel circlips (grade 302 or 316) suit corrosive, food-contact and marine applications, but are slightly less springy than carbon steel equivalents — confirm the application's retention load against the stainless ring's rated force before substituting one for the other. AIMS stocks both carbon steel and stainless circlips across metric and imperial sizes.
How do I choose the right size circlip?
Measure the shaft or bore diameter and match to the circlip nominal size — circlip dimensions reference the shaft diameter for external types, or the bore diameter for internal types, not the ring's outside diameter. If replacing a worn circlip, measure the original groove diameter rather than the deformed ring.
What DIN standards apply to circlips?
Three DIN standards cover the common workshop circlip forms. DIN 471 covers external circlips for shafts — the standard lugged retaining ring that fits a shaft groove and compresses to install. DIN 472 covers internal circlips for bores — the mirror equivalent that spreads to install into a bore groove. DIN 6799 covers E-clips (also called E-rings) — a smaller open-C-shaped retainer that snaps sideways onto a shaft groove without needing pliers. Each standard defines the ring dimensions, groove specifications and installation tolerances by shaft or bore diameter. Metric sizes follow these DIN standards; imperial sizes follow equivalent inch standards, still common on older machinery and imported American equipment, while European and modern equipment typically uses metric.
What is the difference between a circlip, snap ring and retaining ring?
In Australian and UK usage these terms are largely interchangeable — all refer to a spring-steel ring that seats into a machined groove to axially locate a component. Circlip is the traditional Australian/UK term, snap ring is the US preference, and retaining ring is the neutral engineering term used in DIN and ISO standards. There are subtle product distinctions in industry — spiral retaining rings (coiled wire without lugs) and constant-section rings (uniform cross-section) are technically different from the classic lugged circlip — but for general workshop and rigging use, the three names describe the same product. If you've arrived searching for snap rings, this collection is the right place: same DIN-spec sizes from M3 through M150+, in carbon steel and 304 stainless, with matching pliers (US-spec snap-ring pliers fit fine — the tang-hole geometry is interchangeable).
Why does the groove depth and width matter?
Circlips only work if the groove they seat in is machined to the correct depth and width for the ring specification. Too shallow and the ring pops out under load; too deep and the ring cants sideways and loses grip. Groove width should match the ring thickness within a few tenths of a millimetre — a wider groove lets the ring rotate or shift under thermal cycling. DIN 471 and DIN 472 specify the groove dimensions for each ring size. When machining a new groove or replacing a ring, always work to the standard groove spec, not to the deformed geometry of the failed original.
What is a spiral retaining ring and when is it used?
A spiral retaining ring is a coiled flat wire ring — usually two or three turns — that seats in a groove without the lugs of a traditional circlip. Advantages over lugged circlips: no lugs to catch on adjacent components, 360° contact with the groove for better load distribution, higher rotational speeds without dynamic imbalance. Used in high-speed shafts (turbines, high-RPM electric motors) and applications where the lug of a standard circlip would interfere with the mating component. Installation is by winding into the groove rather than compression with pliers.
What's a bowed circlip used for?
A bowed circlip is a flat circlip with a slight bow that provides axial spring force, taking up end float in the retained component rather than simply stopping it — used in precision assemblies where controlled axial preload is needed.
How do I identify a circlip if I don't know the part number?
Measure three dimensions: the shaft or bore diameter the ring fits, the ring thickness (measured across the cross-section, not the outside diameter), and the free-state outside diameter (external) or free-state inside diameter (internal). Match to the DIN 471 or DIN 472 size chart. Note the type — lugged classic circlip, spiral retaining ring, or E-clip. The two lug holes on a classic circlip should measure the same across pairs of the same size. AIMS carries a full range across metric and imperial DIN sizes — see the retaining rings companion range and matching circlip pliers, or read our circlip guide for full selection detail. Bearing installations frequently use circlips — see bearings for the mating range.
How do convertible circlip pliers work?
Convertible circlip pliers reverse their jaws to switch between internal and external circlip use, typically covering a 10-50 mm working size range.
What tool suits circlips in recessed or hard-to-access grooves?
Bent-nose (right-angle) circlip pliers are used for circlips in recessed grooves where straight access is blocked.
What tool replaces circlip pliers when fitting an E-clip?
An E-clip tool or a flat-blade screwdriver replaces circlip pliers when fitting an E-clip, sliding it axially onto the shaft groove.
What working size range do small external circlip pliers typically cover?
Small external circlip pliers (for DIN 471 shaft circlips) typically cover a 3-25 mm working size range.