Kestrel Tripod Clamp Overview Hold your Kestrel Meter securely with this simple mounting clamp that can be attached to tripods or extension poles with a ¼-20 mounting screw. Rubber molding grips the Kestrel securely without scratching the meter. (Also holds smaller smart phones for the occasional selfie.) Maximum 4 in / 11 cm grip opening. Compatible with: Kestrel 1000-3500, Kestrel 4 Series, Kestrel 5 Series