Telescopic stick measure.
Ideal for a quick check and in the hands of experts can be used effectively. Limitations are under 15 cm and over 43 cm for obvious reasons. A comparison tool rather than a measure.
Tele measure Art 161
This telescopic measure has a steel ball on one end and a flat surface on the other. Place the larger flat end towards the boule and the small ball end to the jack for accurate comparison measure. Shown here in closed and close up open mode. Measures between 115mm to 430mm Handy clip on the top. £6.50