A

B

C

D

 E

Nominal Flange Diameter

Nominal Overall Length

Minimum Internal Diameter After Setting

Nominal Outside Diameter

Hole Diameterm

BS 
SI-ZE

ins

mm

ins

mm

ins

mm

BS SI- ZE

ins

mm

ins

mm

18

^3/8

9.53

^11/64

4.37

^13/64

5.16

18C

^3/8

9.53

^1/4

6.35

20

^7/16

11.11

^13/64

5.16

^17/64

6.75

20D

^15/32

11.91

^19/64

7.54

21

^1/2

12.70

^7/32

5.56

^9/32

7.14

21D

^1/2

12.70

^21/64

8.33

22

^9/16

14.29

^15/64

5.95

^11/32

8.73

22D

^9/16

14.29

^23/64

9.13

23

^5/8

15.88

^15/64

5.95

^11/32

8.73

23D

^5/8

15.88

^25/64

^9.92

24

^11/16

17.46

^1/4

6.35

^3/8

9.53

24D

^11/16

17.46

^27/64

10.72

25

^3/4

19.05

^17/64

6.75

^13/32

10.32

25D

^3/4

19.05

^29/64

11.51

26

^13/16

20.64

^9/32

7.14

^7/16

11.11

26D

^13/16

20.64

^31/64

12.30

27

 ^7/8

22.23

^19/64

7.54

^15/32

11.91

27D

 ^7/8

22.23

^35/64

13.10

28

^15/16

23.81

^5/16

7.49

^1/2

12.70

28D

^15/16

23.81

^37/64

14.68

29

1

25.40

^21/64

8.33

^9/16

14.29

29D

1

25.40

^39/64

15.48

30

1^1/8

28.58

^11/32

8.73

5/8

15.88

30D

1^1/8

28.58

^43/64

17.07

31

1^1/4

31.75

^3/8

9.53

^11/16

17.46

31D

1^1/4

31.75

47/64

18.65

32

1^3/8

34.93

^13/32

10.32

^3/4

19.05

32D

1^3/8

34.93

^53/64

21.03

33

1^1/2

38.10

^17/64

10.72

^13/16

20.64

33D

1^1/2

38.10

 ^7/8

23.23

35

1^3/4

44.45

^1/2

12.70

1

25.40

35D

1^3/4

44.45

1^5/64

27.38

36

1^7/8

47.63

^9/16

14.29

1^1/8

28.58

36D

1^7/8

47.63

1^11/64

29.77

37

2

50.80

^39/64

15.48

1^1/4

31.75

37D

2

50.80

1^5/16

33.34

No. 18 is suppled with a plain ring ( not illustrated). No.21 and No.21 can be supplied with plain or turnover rings.