Introducing the SPH: Slim Profile Heads

Sturtevant Richmont is home to some of the most deliberate engineers on the planet. Nothing is ever created without enormous amounts of customer input and feedback. We build the tools for you.

What are SPHs?

The SPH is our "Slim Profile Head" for torque wrenches that use interchangeable heads. Like all of our interchangeable heads, the foundation is the Dovetail. The Dovetail has the basic design when we first patented interchangeable heads for torque wrenches. That was back in 1956.

We've refined the Dovetail a few times since then, but the basic concept is as strong today as it was back then. It is still the most effective approach to delivering maximum torque application using torque wrenches with interchangeable heads.

Like all of our interchangeable heads, we maintain the common centerline. Because we make a cast, one-piece heads, we are focused on the common centerline. Why is the common centerline so important? 

Think about the formula for torque. Part of that equation is the distance between the center of the fastener and the tool length. Change that distance and you change the equation. Change the equation and the torque output changes. Companies use torque wrenches to eliminate variables, not add them. 

Why Create Slim Profile Heads?

Hydraulic assemblies come with their own unique set of challenges. Tight access is near the top of the list. Another challenge is ensuring that each and every hydraulic connector is compliant and the torque value is not changed while tightening another portion of the hydraulic connector. We built our Global 400 and Global 400mp wireless torque controllers as a part of that error-proofing system

Like everything we create, customer demand drove the creation of these interchangeable heads for torque wrenches. Some of our largest customers work with hydraulics as part of their build. 

Our customers told us that they were grinding down our heads so they could fit in tight access points. 

Grinding down heads takes time, costs money, and there is no data on stress points. Plus, you may get some variances between grinding jobs. 

What Makes Slim Profile Heads Important?

As we designed the new heads, we ran computer-simulated, and real-life lab testing on stress points. 

We were able to produce stronger heads with consistent dimensions. As always, we kept the common centerline consistent. With accurate torque values critical to creating compliant hydraulic connections, the common centerline is vital to eliminating assembly variables

Differences You Can "C"

The difference is in the "C" dimension. Take a look. In our world, the "C" dimension is the thickness of the portion of the interchangeable head that engages with the fastener. 

Slim Profile interchangeable Heads for Torque Wrenches



Please note this important common centerline distinction: 

SPH Series Open end interchangeable head for torque wrenches SPHOpen End Interchangeable head for torque wrenches SPHup to 32mm have a common centerline of 1 7/16" or 36.5mm

SPH Series starting at 36mm have a common centerline of 3 7/8" or 98.4mm

SPH Part # Description Capacity



"C" Dimension Difference

OE "C"


Capacity Description OE Part#
853871 OE 19mm SPH 45 Nm 4.37mm 8.33mm 12.70mm 113 Nm OE 19mm 819949
853872 OE 22mm SPH 38 Nm 6.73mm 5.97mm 12.70mm 169 Nm OE 22mm 819951
853873 OE 24mm SPH 71 Nm 6.35mm 6.35mm 12.70mm 254 Nm OE 24mm 819952
853874 OE 27mm SPH 100 Nm 7.37mm 5.33mm 12.70mm 254 Nm OE 27mm 819229
853875 OE 30mm SPH 103 Nm 7.52mm 5.18mm 12.70mm 310 Nm OE 30mm 819956
853876* OE 36mm SPH 152 Nm 10.01mm 5.87mm 15.88mm 350 Nm OE 36mm 819776
853877* OE 41mm SPH 260 Nm 9.65mm 6.23mm 15.88mm 400 Nm OE 41mm 819755
853912 OE 13mm SPH 35 Nm 5.87mm 4.29mm 10.16mm 39 Nm OE 13mm 819945
853913 OE 17mm SPH 25 Nm 5.54mm 4.62mm 10.16mm 79 Nm OE 17mm 819948
853914 OE 32mm SPH 103 Nm 10.69mm 2.01mm 12.70mm 338 Nm OE 32mm 819958
853923* OE 50mm SPH 275 Nm 11.00mm 4.88mm 15.88mm 400 Nm  OE 50mm 819756

*SPH Series starting at 36mm have a common centerline of 3 7/8" or 98.4mm. Be sure to account for that difference when changing common centerline lengths.

The OE Part Number references the same size traditional interchangeable head for torque wrenches. Open end interchangeable head dimensional diagram


Note: All of our open-end heads, ratcheting open-end heads, and slim profile open-end heads have the U-bottom design. We changed from the V-bottom to the U-bottom to increase durability. From an engineering standpoint, a rounded corner distributes the stress vectors more evenly than designs that have intersecting planes. 

If for some reason you want the V-bottom design, we can make that for you as a special. Different pricing, minimum order quantities, and increased lead times apply. 




Our Slim Profile Heads are created in Carol Stream, Illinois by highly competent hands.