Voltage references (especially through-hole ones) are negatively affected by air currents, that induce temperature gradients and ultimately manifest as increased 1/f noise. This cap, designed to cover the reference and its leads, mitigates this effect by completely enclosing the reference.

One variant of the bottom cap is designed to be used with short M3 heated inserts.

Spacing between screw holes is 20mm. Designed for use with M3 bolts.