Type M designation
Keep the ER20M or ER25M code intact; do not silently substitute a standard nut arrangement.
Catalog reference image. Final configuration is confirmed in the quotation.
CNC Tool Holders
Request a quote
C-ERM
Straight Shank ER Collet Chucks Type M
Overview
Type M straight-shank ER collet chucks with 20, 22 or 25 mm shanks. ER20M and ER25M model rows show total length, L1 projection and nut-end diameter.
AvailabilityConfirm before order
Lead timeQuote based
Product description
Type M straight shank ER holders provide the catalog's ER20M and ER25M connection formats on selected cylindrical shanks. Their dimensions are listed as total L, L1, shank C and body D. Select the receiving holder and required reach together, then confirm the Type M nut and collet arrangement for the intended tool.
Cylindrical shank
Match the C dimension to the receiving holder and confirm adequate engagement.
Two length references
Compare both L and L1 with the drawing when checking tool access.
C20-ER20M-150: which length is 150 mm?
The suffix is the catalog L1 dimension. Compare it with total L before specifying the holder:
| Catalog model | L1 | Total L | Shank C / D |
|---|---|---|---|
| C20-ER20M-100 | 100 | 140 | 20 / 28 |
| C20-ER20M-150 | 150 | 190 | 20 / 28 |
C20-ER20M-150 is not a 150 mm overall-length holder. Mark the L and L1 reference points on the drawing when checking engagement and clearance.
Prepare a C20-ER20M-150 quotation request. The form includes these dimensions and fields for shank tolerance, runout and separate collets. Compare the standard C20 ER20 and Type M comparison when checking clearance: the standard C20-ER20 family lists Nut D = 34 mm. These catalog dimensions do not establish nut interchangeability.
Quote the holder and collets as separate items
For a one-piece inquiry, list the holder code and quantity first. Then list any ER20 collets separately. A request for nominal sizes 3 through 13 mm in 1 mm steps means 11 sizes; state whether you want one of each or selected sizes only. This is an inquiry example, not a stocked set or a promise of included accessories. Ask the quotation to identify the supplied nut, collets and wrench, if required.
Use the fillable ER collet inquiry worksheet (PDF, 2 pages) for the separate collet-size list. Include the Type M holder code and drawing with the completed worksheet.
Open the C20-ER20M-150 email checklist to attach a drawing and specify holder quantity, collet bores, inspection requirements and destination. Ask for itemized holder, accessory and freight amounts, including any exclusions.
Agree on runout and shank acceptance before ordering
Ask for separate confirmation of holder runout, collet runout and assembled runout. State the test-pin diameter, measuring distance, receiving holder and maximum acceptable TIR. A component value is not a guarantee for the complete setup.
For the 20 mm shank, request the diameter tolerance and surface finish on the approved drawing. No numeric shank tolerance, roughness, runout grade or speed rating is established by this dimension table. Have the quoted values and inspection method confirmed before accepting the order.
Specifications & model range
Dimensions are in millimeters unless otherwise stated. Confirm the final drawing before ordering.
- Shank diameter C
- 20, 22, 25 mm
- Collet systems
- ER20M, ER25M
- L1
- 60-180 mm
8 catalog rows
Select an underlined catalog reference to include that row in your inquiry.
| Ordering code | Total L, mm | L1, mm | Shank C, mm | D, mm |
|---|---|---|---|---|
| C20-ER20M-60 | 100 | 60 | 20 | 28 |
| C20-ER20M-100 | 140 | 100 | 20 | 28 |
| C20-ER20M-120 | 160 | 120 | 20 | 28 |
| C20-ER20M-150 | 190 | 150 | 20 | 28 |
| C20-ER20M-180 | 220 | 180 | 20 | 28 |
| C22-ER20M-140 | 180 | 140 | 22 | 28 |
| C25-ER20M-140 | 168 | 140 | 25 | 28 |
| C20-ER25M-100 | 150 | 100 | 20 | 35 |
No matching model in this table. Try a shorter code, or send your required size or drawing.
Ranges and slash-separated values describe catalog families, not every possible combination. Confirm the complete model and drawing before ordering.
Application scenarios
Typical selection contexts for this series, not customer project claims. Confirm machine compatibility and cutting conditions for your setup.
Restricted tool access
Comparing the listed Type M envelope with surrounding fixture geometry.
Custom tooling setups
Using a confirmed cylindrical-shank extension in a purpose-designed holder assembly.
Reach replacement
Matching an existing C-ERM extension by its complete dimensions.
Inspection & order review
Specify the dimensions, tolerances and records your order requires. Acceptance criteria must be agreed for the selected model.
Catalog fields to check
- Ordering code
- Total L, mm
- L1, mm
- Shank C, mm
- D, mm
Check the drawing reference faces and units. A catalog size alone does not define a tolerance or an inspection method.
Records to request
List any required dimensional report, material document or model identification photograph in your inquiry. Confirm availability and scope in the quotation.
For a drawing-based part, include the drawing revision and identify the critical dimensions. Website photographs are not inspection reports.
Packaging & delivery
Agree the packing method and photo requirements when confirming your order.
Order-specific photo confirmation
No verified shipment photographs for this series are currently published. Include selected-model, protective-packing and outer-label photos in your order requirements.
Discuss packing requirementsPhotos to confirm before dispatch
Use this checklist to agree what should be documented for your selected model.
- Type M code distinguished from C-ER
- Cylindrical shank and nut protected
- Total and reference lengths traceable to the order
Stock, dispatch date and shipping method are confirmed with the quotation. Website images are not live inventory evidence.
Technical resources
Product specifications
Keep a copy of the current series information for comparison. Confirm the final model and drawing before placing an order.
View specificationsCompare tool-holder connections
Read interface names and ordering codes before choosing a holder.
Read the guideRelated selection information
Browse the existing tooling guides and compare product families before selecting a model.
Browse technical resourcesRelated product series
Compare alternative interfaces and complementary tooling. A related series is not automatically interchangeable.
BT30 / BT40 / BT50
BT ER Collet Holders
Models and specifications
ER8-ER40
ER Precision Collets
Models and specifications
C-ER
Straight Shank ER Collet Chuck Extensions
Models and specificationsCan I replace ER20M with ER20 without checking the drawing?
Do not assume the complete nut and holder arrangement is identical. Confirm the actual Type M geometry.
Does the extension fit any receiving chuck with the same nominal diameter?
Confirm the clamping method, usable engagement, clearance and operation as well as nominal diameter.
Which length should I quote, L or L1?
State both with reference to the drawing. For C20-ER20M-150, L1 is 150 mm and total L is 190 mm; for C20-ER20M-100, L1 is 100 mm and total L is 140 mm. Do not treat the model suffix as overall length.
Is additional reach supplied with a speed guarantee?
No speed or assembled performance rating is established here. The complete extended setup must be reviewed.