As with all racing safety equipment, Head and Neck Restraint (HNR) fitment is critically important, and the Head and Neck Restraint user can increase the risk of injury if they are not fitted properly.  A Frontal Head and Neck Restraint (HNR) restrains the driver’s head relative to the torso during a frontal impact, thereby reducing the loads to the head and neck.

There are different types of HNR systems approved, two of them being the Zamp™ Z-Tech™ Series 4A and Series 1A systems.  Please refer to the general Head and Neck Restraint sizing chart below for proper fitment of these Zamp™ Z-Tech™ Head and Neck Restraint systems.    

This system sizing chart is for ADULT Zamp™ Z-Tech™ Head and Neck Systems.  Please note that according to the factory, YOUTH drivers MAY be able to use the Z-Tech™ Series 4A unit.  However, additional measurements regarding the youth driver are needed.  Please contact the factory for these details and measuring for proper fitment.  

If you need a Head and Neck Restraint system outside of this chart range, please contact our Technical Sales staff for other brand options that may be available for you.  

Properly Measuring Fitment for Zamp™ Z-Tech™ Series 4A & Z-Tech™ Series 1A Head and Neck Restraint Systems


Locate a cloth tape measure and record the following body measurement:

  • A - Neck Diameter - Measure DIAMETER across the front neck line just above the collar while keeping the tape taunt. 

The Zamp™ Z-Tech™ Head and Neck Restraint Systems are ADJUSTABLE and are offered in one size as shown in the fitment chart below.    

Remember, if you DO NOT find a Head and Neck Restraint System that suits you or fits you properly, please contact one of our Technical Sales Specialist and they will work with you to find a solution for you.

Zamp™ Z-Tech™ Series 1A System - Head & Neck Restraint Sizing and Fitment Chart***
Factory Device Size
Adjustable Unit - One Size Fits All (Medium to Large Size)
- Neck Diameter (in.)
4.75" to 7.75"

Zamp™ Z-Tech™ Series 4A System - Head & Neck Restraint Sizing and Fitment Chart***
Factory Device Size
Adjustable Unit - One Size Fits All (Medium to Large Size)
- Neck Diameter (in.)
4.75" to 7.75"


Zamp™ offers two (2) different Z-Tech™ models - The original Z-Tech™ Series 1A HNR system and the new Z-Tech™ Series 4A model.

ZAMP™ Z-TECH™ SERIES 1A - The original Z-Tech™ system offers all the standard safety features as mandated by the SFI® 38.1 Certification Standard and includes the Z-Tech™ Advanced Axis Adjustment feature.

ZAMP™ Z-TECH™ SERIES 4A - The latest system, the Z-Tech™ Series 4A offers all of features of the standard Z-Tech™ model including the Z-Tech™ Advanced Axis Adjustment, but is now SMALLER and features a SUPER-LIGHTWEIGHT design, weighing-in at approximately 925 grams (2-lbs). 

A SIDE NOTE ABOUT SEAT ANGLE -  Many other HNR devices require a special HNR unit depending on racing seat angle.  The Zamp™ Z-Tech™ systems are designed to work with ANY TYPE of seat angle. The drawing below shows all typical racing seat angles that all of the Zamp™ Z-Tech™ HNR systems will easily accommodate.

Zamp™ Z-Tech HNR Systems - Model Applications for Head & Neck Restraint Systems***
Seat Angle
Typical Racing Application
Applicable Z-Tech™ Model


Adult Size Zamp™ Z-Tech™ Systems Work with All Types of Race Cars and Various Seat Configurations including Sprint Cars - East Coast Modifieds - Asphalt Late-Models - Dirt Late-Models - Street Stocks - Legends - IMCA/UMP/Wissota Modifieds - Full-Bodied Drag Cars and Dragsters - Sedan Sportscars - Drag Boats - Open Wheel/Road Race Cars including Formula Ford®, Formula Mazda®, Barber Dodge® and Infiniti® Pro
Zamp™ Z-Tech™ Series 1A

 Zamp™ Z-Tech™ Series 4A

TECHNICAL CREDIT AND ACKNOWLEDGEMENT: The above HNR, seat and helmet technical information and illustrations were compiled using excerpts from the Federal Internationale De L'Automobile (FIA) 'Guide and Installation Specifications for FHR Devices in Racing Competition' document published in June 2017.  To review this full PDF document click here or visit the FIA website Safety Section at (both links open new browser window).

Racecar Engineering™ Has All of Your Racing Safety Gear Needs Covered

Please remember that Racecar Engineering™ carries both Zamp™ Z-Tech™ Head and Neck Restraint systems and related replacement parts.  On top of that, we also have in stock and ready to ship, the entire product line of Zamp™ safety equipment including racing suits, racing helmets and related accessories.

Browse our wide selection of safety products and buy online today.  If you have questions about choosing the right safety equipment for your motorsports segment, please contact one of our Technical Sales Associates for assistance.

At Racecar Engineering™ we make every attempt to be every racer's 'One-Stop Safety Shop'.

Return To:  Main Technical Center Page  |  Head and Neck Restraint Info/Sizing Chart Page - All Brands

Related Tech Safety Topics:  Racing Helmets | Racing Suits | Driving Gloves | Driving Shoes | Racing Seats

*** HEAD & NECK RESTRAINT SYSTEM SIZING/FITMENT CHART DISCLAIMER: This head and neck restraint system sizing/fitment chart has been created by Racecar Engineering™ for our customer's reference and ease-of-use using the latest fitment information available from the factory.  Please always refer to the factory website, factory printed materials and factory personnel advice for the latest head and neck restraint system information about their brand of safety product.  The Zamp factory website can be accessed directly at (link opens new page) - Racecar Engineering™ is not responsible for any typographical errors contained in this head and neck restraint system sizing chart/fitment material or the end-user's failure to verify & follow factory fitment specifications.