HumanscaleKeyboard Systems: 5G Standard Mechanism - Standard 21.625" Track

I'm writing this review on the Humanscale 5G keyboard arm mechanism. There several choices of platforms to attach to the arm mechanism. I've been using the 5G arm for I'd guess about 10 years now ( might even be more than that ). I have a different keyboard & mouse tray for oversized keyboard.The arm easily lifts with your fingertips lifting on the front of the keyboard tray, and lowers easily by gently pushing down on the bump at the top of tray and lifting the front a bit as you would while raising tray. I have nothing but praise for the Arm mechanism. I never use the upward tilt, but it's easy to raise the angle of the keyboard tray by twisting the handle.Most highest praise however goes to the Humanscale company. They stand behind their product well beyond what I expected. After owning the Keyboard arm / tray for 3 or 4 years, it was working fine, but the smooth action up and down became a bit jerky when I raised it with one touch fingertip lifting. I put a call into Humanscale customer service number asking if I could lubricate it somehow, and their response was they would schedule a guy to come to my home office to fix or replace it for me. I was surprised, and let the Service rep know that I was a simple home office and would not be buying more.. asking if he could just tell me what I could do, and he insisted that a rep come out. ( the warranty when I bout it was lifetime, looks like they lowered it to 15-20 years )The Rep came to my home in a van, and showed me where to lift a cap and squirt some WD40 into spring mechanism followed by raising and lowering arm a few times. After this procedure, the lift worked flawlessly again just like new. Satisfied well beyond my expectations. Every 2 or 3 years, I need to squirt some WD40 under the cap, but outside of that, it gets used daily and keeps on chugging moving the keyboard up and down, rotating, and sliding in and out from desk a few times every day. .Saved me from Carpel Tunnel that I was starting to get from typing with keyboard on desktop. Great investment I'd highly recommend with anybody using a keyboard couple hours a day.