Behold! Each knee extension is made from 2 pieces of 1/16 inch Lexan (polycarbonate), and 1 piece of 5/32 inch of acrylic plastic. The pieces of Lexan sandwich the acrylic, and all 3 parts are held together with superglue. Holes of appropriate size were drilled. The top part is held onto Soundwave's knees with new screws, while the bottom part is held on with Soundwave's original screw arrangement. It is a sturdy mod, and the plastics can be painted as desired (I have yet to muster the will to do so). It is not a permanent or destructive mod at all, as the extensions can be easily removed, and the knees restored to their original armature. I point this out because the extensions do sacrifice his alt mode. Each is about 1 inch in length, but Soundwave looks beyond silly if you poise him with the extensions upright. He looks better if they're bent so as to give him bird legs.