ELECTRONIC CONTROLLER

To permit external adjustment of a potentiometer (3) having an adjustment head (4), and located within a sealed housing (1), while permitting placement of an adjustment insert (7) from the outside of the housing through a bore (6) thereof, and compensate for manufacturing and positioning tolerances, the insert element is a unitary structure of a tough plastic, such as polyamide (nylon), sealingly inserted through the opening and retained in the opening by snap-over hooks (13) engaging over the inner wall (25) of the housing, and retaining a screw head (8) of the insert element therein. Longitudinal and transverse deviation from alignment of the axis of the opening (6) and the rotation axis of the adjustment element (4) of the potentiometer is obtained by resiliently deflectable cross-joints (14, 14'; 17, 18) formed in an intermediate portion of the insert element, which cross-joints are connected by a S-shaped resiliently deflectable connecting portion. The end (19) of the insert element, fitting against the adjustment portion (4) of the potentiometer, and/or a screwdriver blade-like engagement blade (24) are preferably formed with self-aligning engagement surfaces (20) to permit self-seeking positioning of engagement of the insert with the potentiometer in spite of possible initial, or later misalignment due to tolerances.