Bridle (double reed)
Clip at the base of the 2 reed blades; It is manipulated in order to increase/decrease their Mouth, thus influencing the sound and pitch of the reed.
Generally made of metal.
Garvin, Wilbert: The Irish bagpipes: their construction and maintenance [Belfast 1978, Blackstaff Press]. Foreword by Breandán Breathnach. Kells, 1988 (2), p.20.