Design Features

ETA Assembly Arms

GOOD DESIGN, PRECISION MACHINING & CAREFUL ASSEMBLY make ETA the Torque Arm solution for many years of efficient production.

ETA Arms come with a warranty against excessive wear and part breakage under normal industrial use for a period of 5 years. This 5 year warranty includes all bearings, bushings, shafts, and float cylinder for an unlimited amount of use ! See Warranty Page for details.


  1. Precision Machined Pivot Points. Permanently lubricated bearings are hand fit to their ground shafts within 0.0003 inches (.007mm) or better and pivot on Roller Thrust Bearings for the most rigidity and smoothest movement possible. WARRANTIED 5 YEARS  AGAINST EXCESSIVE WEAR. All components are machined, ground and assembled right here in Pennsylvania, USA.
  2. ETA Air Cylinder Floatation will Outlast and Outperform sealed gas springs, coil springs and spring loaded cable balancers many, many times over. With clean, dry compressed air, rated life-cycle of our float cylinder is a minimum of 50,000,000 (50 million) rundowns! Our Cylinder is Mounted Upright so that float is consistent as you raise and lower the arm without the “toggle” feel experienced on sealed gas springs and other’s air cylinder mounted on a bias inside the arm. And our air cylinder’s performance will not degrade gradually the way sealed gas springs do. For this reason we use our air cylinder float on all arm models, even those for use with battery or corded electric tools. The amount of air consumed for balancing an ETA arm with your tool is less than 0.03 CFM. Cylinders are made for ETA in the USA.
  3. Float Regulator is Easily Adjusted in seconds with the twist of the knob. Set it once and forget it. No further adjustment or maintenance for many millions of cycles. Regulators are made for ETA in the USA.
  4. Operator has uncluttered view of work area. All moving parts and pneumatics are in the back of the arm so there is a more open view of the work being done. The top edge of our Forearm (front half of arm) is only 1 inch (25.4mm) wide.
  5. All Tool Holders with moving parts are built with hardened steel components and Grade 8 hardware, permanently lubricated bushings and roller thrust bearings. We never use aluminum as a dynamic wear surface. All ETA Tool Holders fit all ETA Forearms. All ETA Forearms also have ¼ NPT Threads for direct air tool connection if needed. For custom tooling and fixtures, our Forearms are easy to adapt to because they always remain parallel to your bench top. All ETA Tool Holders are machined, ground and assembled right here in Pennsylvania, USA.
  6. Check Valve prevents arm from falling rapidly if there is a sudden loss of air supply. Check Valves are made in the USA.
  7. Mounting Post is 1-1/4 npt Iron Pipe which makes it easy to accommodate different mounting locations and positions, including overhead, and still have the arm in the correct work zone. For floor or overhead mounts from long distances we offer our B250 Heavy Duty Base.
  8. Welded Steel Mounting Base with 3 leveling screws and 3 mounting holes for 3/8″ (M8) bolts. Post Threads are 1-1/4 npt. ETA Bases are forged, cut & welded for ETA right here in Pennsylvania, USA.
  9. On PA-Series Arms for air powered tools a braided polyurethane tool supply hose with reusable brass swivel fittings is included.
Young boy demonstrating easy movement of model EL815-UV with 10 LB (4.5 Kg) weight