Metric internal circlip sizes and dimensions are shown in the following chart according to DIN 472 standard.

Internal circlips are retaining rings for securing mechanical elements (e.g. bearings) in bores. Circlips are installed into a groove and creating a shoulder that retains the assembly. Lugs with holes are provided for easy fitting and removal with pliers.

Some important notes from the DIN 472 standard:

- Material: C 67 , C 75 or Ck 75 spring steel in accordance with DIN 17222.

- Finish: Circlips must be without burr. Circlips are normally supplied corrosion-proof. Details are given in DIN 472.

- Designation: Bore diameter (nominal dimension) and circlip thickness s (Ex: Circlip DIN 472 - 40 x 1,75)

Metric Internal Circlip Sizes Chart:

Circlip Type
Bore Diameter (d1)


Internal Circlips - Metric DIN 472
Parameter Value
Nominal Bore Diameter [d1] --- mm
Thickness of the Circlip [s] --- mm
Thickness Upper Deviation [Sup_dev] ---
Thickness Lower Deviation [Slow_dev] ---
External Diameter of Circlip (Not under tension) [d3] ---
External Diameter Upper Deviation [d3_up_dev] ---
External Diameter Lower Deviation [d3_low_dev] ---
Maximum Radial Width of the Lug [amax] ---
Beam (Radial Width of Circlip Opposite the Aperture) [b ≈] Note 1 ---
Diameter of Lug Holes [d5_min] ---
Weight of 1000 pieces [w ≈] --- kg
Groove Diameter [d2] --- mm
Groove Diameter Upper Deviation [d2_up_dev ] ---
Groove Diameter Lower Deviation [d2_low_dev] ---
Groove Width [m] ---
Groove Depth with Nominal Sizes of d1 and d2 [t] ---
Minimum Edge Margin [nmin] ---
Supplementary Data Note 2
Minimum Symmetrical Diameter of Bore during Fitting [d4] --- mm
Load-bearing Capacity of Groove at a Yield Point of the Grooved Material of 200 MPa [FN] --- kN
Load-bearing Capacity of Circlip with Sharp-edged Abutment of the Pressure Part [FR] ---
Edge Chamfering Distance of the  Surface abutting the Circlip [g] --- mm
Load-bearing Capacity of Circlip for Abutment with Edge Chamfering Distance g [FRg] --- kN
Nominal Size of Pliers according to DIN 5254 --- ---

Note 1 : Dimension b shall not exceed dimension a max.

Note 2 : Supplementary data is applicable only to circlips in spring steel in accordance with DIN 17222.

Note 3 : The load-bearing capacities (FN, FR, FRg) contain no safety against yielding under static stress nor against fatigue fracture under fluctuating stress.

Note 4 : Details of load-bearing capacities calculation for different parameters are given in DIN 472.


  • DIN 472 , Circlips (retaining rings) for bores - Normal type and heavy type