Choosing a Threading Toolholder

Browse external and internal threading toolholders. Compare the holder dimensions, insert size and matching spare parts before selecting a model.

All dimensions are in mm unless otherwise stated. Dmin: minimum bore diameter; L: overall length. Other symbols follow the individual drawings; α is given in degrees.

The square symbol (□) is a placeholder in an insert designation, not a complete order code. A dash (-) or slash (/) indicates that no value or part reference is listed in the catalogue. Confirm the complete holder and insert combination before ordering.

How to Read the Toolholder Code

Use the example below to identify the main fields in the toolholder code. Expand the code reference for detailed meanings and size codes.

Example: S E R 2020 K 16

Toolholder Code Reference

Field	Code	Meaning
1	S	Insert clamping: screw; D = clamp plate
2	E	External threading; I = internal threading
3	R	Right-hand holder; L = left-hand
4	2020	Square shank: 20 脳 20 mm; 0020 denotes a 20 mm round shank
5	K	Holder length code: 125 mm
6	16	Insert size code: nominal L = 16 mm, I.C. = 3/8 inch
7	Optional suffix	Additional holder features, where specified

Holder Length Codes

Code	Length (mm)
D	60
F	80
H	100
K	125
L	140
M	150
P	170
R	200
S	250
T	300
U	350
V	400

Threading Insert Size Codes

Size code	I.C. (inch)
06	5/32
08	3/16
11	1/4
16	3/8
22	1/2
27	5/8
33	3/4

I.C. is the diameter of the inscribed circle. Sizes with a U suffix are catalogue variants; use the exact insert designation listed for the holder.

R and L identify the holder hand. The thread produced also depends on the setup and feed direction.

External Threading Toolholders

SER/L – External Threading

Model	h	b	L	f	h1	L1
SER/L1212H16	12	12	100	16	12	20
SER/L1616H16	16	16	100	20	16	22
SER/L2020K16	20	20	125	25	20	22
SER/L2525M16	25	25	150	32	25	22
SER/L3232P16	32	32	170	40	32	22

Matching inserts and parts

Models	Insert	Shim	Screw	Wrench
SER/L1212H16	16/ER/L□□	–	M3.5×9	T8
SER/L1616H16 SER/L2020K16 SER/L2525M16 SER/L3232P16	16/ER/L□□	STM1603	M3.5×12	T15

B-SER/L – External Threading

Model	h	b	L	f	h1	L1
B-SER/L1212H16	12	12	100	16	12	20
B-SER/L1616H16	16	16	100	20	16	22
B-SER/L2020K16	20	20	125	25	20	22
B-SER/L2525M16	25	25	150	32	25	22
B-SER/L3232P16	32	32	170	40	32	22

Matching inserts and parts

Models	Insert	Shim	Screw	Wrench
B-SER/L1212H16	16/EP/L□□	–	M3.5×9	T15
B-SER/L1616H16 B-SER/L2020K16 B-SER/L2525M16 B-SER/L3232P16	16/EP/L□□	STM1603	M3.5×12	T15

DER – External Threading

Model	Insert size	B = H	L	F
DER1212H16	16	12	100	16
DER1616H16	16	16	100	16
DER2020K16	16	20	125	20
DER2525M16	16	25	150	25
DER2525M15	22	25	150	25

Matching inserts and parts

Models	Clamp screw	Clamp	Shim screw	Torx wrench	RH shim	LH shim
DER1212H16 DER1616H16 DER2020K16 DER2525M16	S16	C16	A16S	K16	AE16	AI16
DER2525M15	S22	C22	A22	K22	AE22	AI22

SER – External Threading, Alternate Design

Model	Insert size	B = H	L	F
SER1616H16	16	16	100	18
SER2020K16	16	20	125	22
SER2525M16	16	25	150	27
SER2525M22	22	25	150	27.5

Matching inserts and parts

Models	Clamp screw	Torx wrench
SER1616H16 SER2020K16 SER2525M16	S16S	K16
SER2525M22	S22S	K22

Internal Threading Toolholders

SNR/L – Internal Threading

Model	Dmin	D	H	L	L1	f	α (°)
SNR/L0010K11	13	10	9	125	22	7.2	15
SNR/L0012M11	15	12	11	150	22	8.5	15
SNR/L0013M16	16	16	15	150	32	10.2	17
SNR/L0016M16	19	16	15	150	40	11.7	15
SNR/L0020Q16	24	20	19	180	40	13.7	21
SNR/L0025R16	29	25	24	200	45	16.2	21
SNR/L0032S16	36	32	30	250	50	19.7	15
SNR/L0040T16	44	40	38	300	55	23.7	15
SNR/L0050U16	54	50	48	350	60	28.7	15

Matching inserts and parts

Models	Insert	Shim	Screw	Wrench
SNR/L0010K11 SNR/L0012M11	11/NR/L□□	/	M2.5×6	T8
SNR/L0013M16 SNR/L0016M16	16/NR/L□□	/	M3.5×9	T15
SNR/L0020Q16 SNR/L0025R16 SNR/L0032S16 SNR/L0040T16 SNR/L0050U16	16/NR/L□□	STM1603	M3.5×12	T15

SIR – Internal Threading

Model	Insert size	D	D1	Dmin	L	L1	F
*SIR0010M11-A16	11	16	10	12	150	28	7.4
*SIR0012M11-A16	11	16	12	14	150	32	8.2
*SIR0013M16-A16	16	16	13	17	150	37	9.2

Matching inserts and parts

Models	Clamp screw	Shim screw	Torx wrench	RH shim	LH shim
*SIR0010M11-A16 *SIR0012M11-A16	M2.5×6	–	T8	–	–
*SIR0013M16-A16	M3.5×9	–	T15	–	–

CNR – Internal Threading

Model	Dmin	d	f	L	L1	H	α (°)
CNR0007K08	10	7	5	125	16	6	18
CNR0008K08	11	8	5.4	125	16	7	18
CNR0010M11	13	10	6.4	150	16	9	15
CNR0012M11	16	12	8.5	150	16	11	15
CNR0014Q11	17	14	8.9	180	20	13	17
CNR0016Q16	20	16	10.2	180	20	15	15

Matching inserts and parts

Models	Insert	Screw	Wrench
CNR0007K08 CNR0008K08	08NRM□□	M2.5×5	T8
CNR0010M11 CNR0012M11 CNR0014Q11	11NRM□□	M2.5×9	T8
CNR0016Q16	16NR□□	M3.5×9	T15

DIR – Internal Threading

Model	Insert size	D	D1	Dmin	L	L1	F
DIR0020R16	16	20	20	24	170	–	13.7
DIR0025R16	16	25	25	29	200	–	16.2
DIR0032S16	16	32	32	36	250	–	19.7
DIR0025R22	22	25	25	29	200	–	18.1
DIR0032R22	22	32	32	38	250	–	20.2

Matching inserts and parts

Models	Clamp screw	Clamp	Shim screw	Torx wrench	RH shim	LH shim
DIR0020R16 DIR0025R16 DIR0032S16	S16	C16	A16	K16	AI16	AE16
DIR0025R22 DIR0032R22	S22	C22	A22	K22	AI22	AE22

SER Toolholder Assembly

Reference assembly for the SER design shown in the catalogue. Other holder designs may use different parts.

1: Screw; 2: Insert; 3: Shim.

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