This is a direct Replacement for a Komatsu  part no. KAB 411 Seat - The Price online includes the Head Rest, Left and Right Arm rests. The HD Version has one more Dampener  in it then the regular system for  even more comforttable  ride. 

Features 

•Medium Adjustable Backrest

• Left Hand Side Control for Recline Adjustment

• Adjustable Air Lumbar

• Adjustable Air Lumbar

• Document Holder

• 7° Seat Tilt Adjustment in 3 Positions

• 50mm Seat Cushion Length Adjustment

• Heavy Duty Mechanical Suspension

• Up to 130kg (290lbs) Manual Weight Adjustment

• 60mm (2.375”) Suspension Height

Adjustment in 3 Positions

• 100mm (4”) Suspension Stroke

• Adjustable Upper Double Locking Slide

Rails with 5mm Reinforcement Bars

Extra options Available not included with  this price

2.5” Standard Armrest Left • 570-34L( extra not included )

• 2.5” Standard Armrest Right • 570-34R (extra not included)

• Adjustable Headrest B/G Cloth • 570-22 (extra and not included)

Made in Canada