EPT Adjustable Click Torque Wrenches

Quick Answer

The EPT-Series is a line of adjustable click torque wrenches designed for applications where the torque requirement may change between fasteners or tasks.

An external, laser-marked dual scale allows the operator to adjust the torque setting directly on the wrench. When the selected torque is reached, the wrench produces a click that can be heard and felt, signaling the operator that the target torque has been achieved.

The EPT lineup includes nine models covering torque ranges from 20 lbf.in to 750 lbf.ft, with square drive sizes from 1/4" to 1".

Who This Is For

Manufacturing engineers
Process engineers
Quality engineers
Maintenance technicians
Field service technicians
Assembly operators
Automotive manufacturing and service
Aerospace manufacturing and maintenance
Energy and industrial facilities
General industrial production

When Should You Use This?

Use the EPT when:

Multiple torque settings are required with the same wrench
Operators need to adjust torque between fastening tasks
A visible torque scale is preferred
Both American and S.I. torque scales are useful
An audible and tactile indication of reaching torque is required
Clockwise and counterclockwise ratcheting operation is needed
Field service or maintenance requires a versatile torque wrench
Medium- or high-torque fastening is required

The adjustable design makes the EPT especially useful when fasteners of different sizes or applications require quick changes to the torque setting.

When Should You NOT Use This?

The EPT may not be the best choice when:

The same torque value is used continuously and operator adjustment should be restricted
A preset wrench is preferred for production error-proofing
A break-over or cam-over mechanism is required
Electronic torque measurement or fastening data collection is needed
Torque-angle measurement is required
A visual digital torque reading is required

For repetitive production fastening at a single torque value, a preset torque wrench may provide better control over operator adjustment.

How the EPT Works

The EPT uses an adjustable spring-loaded click mechanism to indicate when the selected torque has been reached.

During operation:

The operator selects the required torque using the external scale and graduation collar.
The positive locking mechanism secures the selected setting.
The appropriate socket is installed on the square drive.
The operator applies force smoothly to the fastener.
When the selected torque is reached, the wrench produces a click that can be heard and felt.
The operator stops applying force after the click.

Result:

Adjustable torque control
Clear indication when target torque is reached
One wrench can support multiple torque requirements
Improved consistency during manual fastening
Greater flexibility for service, maintenance, and production applications

The spring-loaded pull-down ring locks the selected setting to help prevent incidental adjustment during fastening.

Core Features

Adjustable click torque wrench
External torque adjustment scale
Dual American and S.I. scales
Laser-marked scale for readability
Micrometer-style graduation collar
Positive locking mechanism with spring-loaded pull-down ring
Audible and tactile click when torque is reached
Bi-directional ratchet head
Square drive
All-steel construction
Corrosion-resistant finish
Lightly knurled non-slip grip
Designed for field service, maintenance, and production
Torque capacities covering 20 lbf.in through 750 lbf.ft
Preferred and certified ranges in accordance with ISO 6789 at ±4% of indicated setting

Available Models

The EPT-Series includes nine adjustable click wrench models with different torque ranges and square drive sizes.

EPT Model Chart

Model	Item #	American Torque Range	S.I. Torque Range	Drive Size
EPT100i	280050	20–100 lbf.in	2.8–11.9 N·m	1/4" Sq. Dr.
EPT250i-D	280033	50–250 lbf.in	6.2–28.8 N·m	1/4" Sq. Dr.
EPT250i-A	280034	50–250 lbf.in	6.2–28.8 N·m	3/8" Sq. Dr.
EPT75F	280035	15–75 lbf.ft	23.7–105.1 N·m	3/8" Sq. Dr.
EPT150F	280036	10–150 lbf.ft	20.3–210.1 N·m	1/2" Sq. Dr.
EPT250F	280037	30–250 lbf.ft	47.4–345.7 N·m	1/2" Sq. Dr.
EPT400F	280038	80–400 lbf.ft	142.3–559.2 N·m	3/4" Sq. Dr.
EPT550F	280039	110–550 lbf.ft	183–779.5 N·m	3/4" Sq. Dr.
EPT750F	280040	150–750 lbf.ft	237.2–1050.6 N·m	1" Sq. Dr.

The product data sheet lists nine models and drive sizes ranging from 1/4" to 1".

Graduation Scale

Each EPT model uses an external scale and graduation collar to set the desired torque.

Model	American Graduation	S.I. Graduation
EPT100i	0.5 lbf.in	0.1 N·m
EPT250i-D	1 lbf.in	0.1 N·m
EPT250i-A	1 lbf.in	0.1 N·m
EPT75F	0.5 lbf.ft	0.5 N·m
EPT150F	1 lbf.ft	1 N·m
EPT250F	2 lbf.ft	2 N·m
EPT400F	2.5 lbf.ft	2.5 N·m
EPT550F	2.5 lbf.ft	5 N·m
EPT750F	5 lbf.ft	5 N·m

Model Selection Guide

If you need:	Recommended Model
Lowest EPT torque range	EPT100i
Up to 250 lbf.in with 1/4" drive	EPT250i-D
Up to 250 lbf.in with 3/8" drive	EPT250i-A
Up to 75 lbf.ft	EPT75F
Up to 150 lbf.ft	EPT150F
Up to 250 lbf.ft	EPT250F
Up to 400 lbf.ft	EPT400F
Up to 550 lbf.ft	EPT550F
Highest EPT torque capacity	EPT750F

The EPT250i-D and EPT250i-A have the same torque range, but their square drives differ: the EPT250i-D uses a 1/4" square drive, while the EPT250i-A uses a 3/8" square drive.

Ratchet & Drive Configuration

The EPT-Series uses square-drive ratchet heads sized according to the torque capacity of the wrench.

EPT100i: 60-tooth ratchet
EPT250i through EPT750F: 48-tooth ratchet
Drive sizes: 1/4", 3/8", 1/2", 3/4", and 1"
Bi-directional ratchet: allows switching between clockwise and counterclockwise operation

Setting the Torque

The EPT uses a dual-scale system and graduation collar to adjust the torque value.

Determine the required torque value.
Pull down the spring-loaded locking ring.
Rotate the handle to adjust the torque setting.
Use the laser-marked main scale and graduation collar to select the required value.
Release the locking ring to secure the setting.
Install the appropriate socket on the square drive.
Verify the wrench setting as required by your torque control procedures.
Apply torque smoothly until the click is heard and felt.
Stop applying force when the wrench clicks.

The locking mechanism helps prevent the torque value from being unintentionally changed during use.

Calibration & Accuracy

The preferred and certified ranges of the EPT-Series are in accordance with the requirements of ISO 6789 at ±4% of the indicated setting.

The EPT should be periodically verified and calibrated as part of the facility's torque control program. Mountz's EPT FAQ notes that ISO 6789-1:2017 calls for a maximum of 5,000 cycles before recalibration.

Common Applications

The EPT-Series is commonly used in:

Field service
Equipment maintenance
Industrial production
Automotive assembly and maintenance
Aerospace maintenance and assembly
Construction equipment
Energy applications
Chemical processing facilities
Industrial machinery
Applications requiring multiple torque settings

Mountz specifically positions the EPT for field service, maintenance, and production environments, with its all-steel construction supporting demanding industrial use.

Use Cases (Real-World Examples)

Field Service

Problem: A technician needs to service multiple fasteners with different torque requirements using a limited tool kit.

Solution: The EPT's adjustable scale allows the technician to change torque settings on the same wrench instead of carrying a separate preset wrench for every torque value.

Equipment Maintenance

Problem: Maintenance procedures involve fasteners with several different torque specifications.

Solution: The external dual scale and graduation collar allow the EPT to be adjusted as torque requirements change throughout the maintenance procedure.

Production Fastening

Problem: A workstation requires controlled manual fastening at multiple torque settings.

Solution: The EPT provides adjustable torque control with an audible and tactile click to indicate when each selected torque value has been reached.

High-Torque Industrial Fastening

Problem: Large industrial fasteners require substantially higher torque than smaller assembly applications.

Solution: The EPT lineup extends through the EPT750F, providing a range of 150–750 lbf.ft with a 1" square drive.

Maintenance

Keep the wrench clean and free of debris.
Inspect the ratchet head, square drive, handle, locking mechanism, and scale for wear or damage.
Periodically verify torque output using a calibrated torque analyzer.
Recalibrate according to your facility's calibration schedule and applicable quality requirements.
Apply torque smoothly and consistently during use.
Remove damaged or improperly functioning tools from service until inspected or repaired.

Important: After use, return the EPT to its minimum scale value before storage. This helps preserve the internal spring and supports longer tool life with high precision.

Integration & Advanced Notes

Mechanical adjustable torque wrench requiring no electrical power
External adjustment allows multiple torque values with one tool
Dual American and S.I. scales
Micrometer graduation collar provides incremental adjustment
Positive locking mechanism helps prevent incidental setting changes
Bi-directional ratchet head
Audible and tactile torque indication
Square drive sizes from 1/4" through 1"
60-tooth ratchet on EPT100i
48-tooth ratchet on EPT250i through EPT750F
Designed for field service, maintenance, and production applications
No electronic data collection or traceability

Media & Supporting Content

Need Help?

Contact Applications Engineering for setup guidance
Speak with Sales for product selection
Call us:
- North America:(408) 850-9978
- International: +44 1428 741756

EPT Adjustable Click Torque Wrenches – FAQ & User Guide