Ultradyne UD Adjustable Thumb Rest Black. Resting your thumb on the same side as your trigger finger allows for a straight trigger pull without any torque or torsion of the grip. Providing this rest with adjustment gives ultimate customization to ensure every user can be comfortable. Specifications for Ultradyne UD Adjustable Thumb Rest: Manufacturer: Ultradyne Color: Black Fabric/Material: Nylon Features of Ultradyne UD Adjustable Thumb Rest MLOK hardware included Textured for comfort Package Contents: Ultradyne UD Adjustable Thumb Rest Installation Hardware Included Ultradyne UD20176: UD Adjustable Thumb Rest Black