4 extension arms are not needed

Stacked 49'' Stability: Dual monitor stand keeps two 49” ultrawide monitors in a vertical stack with no forward tilt or sag

Smooth Lifting Power - Effortlessly raise or lower your screen with a premium gas spring arm—tested over 2

<Swivel TV mount moves flexibly>Put your TV at a comfortable angle to watch with this swivel TV mount

<Securely Mounted>3 non-slip adjustable straps firmly attach the Bluetooth speaker to 5"-7" circumference rail

MOUNTUP Triple Monitor Stand Mount - 3 Monitors Desk Mount for Computer Screens Up to 27 inch, Triple Monitor Arm with Gas Spring, Heavy Duty Monitors Stand, Each Arm Holds Up to 19.8 lbs, White Monitor Arm 4 extension arms are notUniversal Compatibility: Triple monitor stand perfectly fits most flat or curved LCD computer screens up to 27", including but not limited to 27, 25, 24, 23, 22, 21. 5, 21, 20, 19, 17 inches displays. Each arm supports a weight of 4. 4 19. 8 lbs, compatible with VESA patterns 75x75mm and 100x100mm. Support C clamp (desk thickness within 0. 39'' 3. 15'') and grommet mount (desk thickness&hole diameter within 0. 39'' 1. 97'') mounting installation.