I’m using LeftShoulderAttachment for my left upper arm accessory, and LeftElbowRigAttachment for left lower arm, same with right side with right shoulder and right elbow. While the right arm looks completely fine, the left upper arm and left lower arm seems to be glued together. The material is smooth plastic.
https://gyazo.com/b82d5cf6bfda4485ca3180d696046ac0
https://gyazo.com/869c82a672768bf0c432221c6c1d82bf