Patent drawing for Glaser guitar string bender, figure 2, patent 4354417, title Tone Changer for Stringed Instrument.
Patent drawing for Hennessey guitar string bender, figures 1, 2 and 4, patent 4658693, titled Rear operated control device for guitar.
Patent drawing for Parsons-White String Bender, figures 2, 3 and 4, patent 3,512,443, title Shoulder Strap Control for String Instruments.
Grand piano action Public domain photograph related to music, performing arts, free to use, no copyright restrictions image - Picryl description
Upright piano action Public domain photograph related to music, performing arts, free to use, no copyright restrictions image - Picryl description