Interchangeable Head Overview

Virtually all S/R interchangeable heads are cast as a single piece from alloy steel. The manufacturing method provides strength and durability rarely attained by the more common “cut and weld” method. To achieve constant torque values when changing heads, exact lever length must be maintained. Virtually all S/R heads share a precise distance from end of wrench to center of fastener. This is referred to as a “Common Center Line” and is very difficult to maintain using the cut and weld construction method.

The unique S/R dovetail design used to join head and wrench provides an exceptionally strong connection and allows complete interchangeability. Competing manufacturers find it necessary to increase the size of the mating connection at higher torque values, creating duplication of wrenches and heads while losing interchangeability.

The S/R system avoids this needless increase in purchase and ownership costs, contributing to operational flexibility and enhancing your return on investment!

Below is a short explanation of each type of S/R interchangeable head. Click on any picture to be taken to a page with a larger image and technical details for the head type.

Square Drive This series is designated “SD”. Ideal when: Calibrating the wrench on a torque tester. A socket can be used to engage the fastener. A small amount of rotation will be needed to attain the desired torque.	Square Drive Ratchet This series is designated “SDRT”. Ideal when: A socket can be used to engage the fastener. A higher amount of rotation will be needed to attain the desired torque.
Open End This series is designated “OE”. Ideal when: Entire hex of fastener or fitting cannot be engaged. A moderate level of head strength (torque level) is needed.	Ratcheting Open End This series is designated “ROE”. Ideal when: Entire hex of fastener or fitting cannot be engaged. Significant rotation of the fastener or fitting is required (more than 120 degrees). A lower level of head strength (torque level) is needed.
Box Head This series is designated “BH”. Ideal when: A socket cannot be used. The entire hex of the fastener or fitting can be engaged. A high level of head strength (torque level) is needed.	Flare Nut This series is designated “FN”. Ideal when: Working on pneumatic, hyrdraulic or other connections involving tubing. There is not room to fit an OE or ROE head into the space at the connection.
Ratcheting Flare Nut This series is designated “RFN”. Excellent when: Working on pneumatic, hyrdraulic or other connections involving tubing. There is not room to fit an OE or ROE head into the space at the connection. Ratcheting of the connector is needed.	Hex Drive This series is designated “HD”. Ideal when tightening socket head fasteners.
Adapter for DIN Style Heads This series has two sizes: 9mm x 12mm and 14mm x 18mm. Ideal when you have heads with DIN-style rectangular connectors and need to connect them to S/R interchangeable head torque wrenches.	Adapter for Standard Tooling This series is designated “STA”. Ideal when you need to make a custom head and wish to use it with an S/R interchangeable head torque wrench.
Adapter for Round Style Heads This series has two sizes: “J” and “Y”. Ideal when you have heads with round connectors and need to connect them to S/R interchangeable head torque wrenches.	Extension - Straight This series is designated “LTCE”. Ideal when a greater straight length between the head and the tool is needed.
Extension - 15 Degree Angle This series is designated “LTCE” with a length and angle suffix. Ideal when an angled length between the head and the tool is needed.
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