Concise Circular Slide Ruler Alpha 4300

Item is in good working condition. Shows signs of use and wear. Manual cover has come loose from staple. Please see all provided photographs for a representation of the item you will receive.
Black sleeve shows No. 300. Manual shows No. 28. Ruler shows Alpha 4300.

Diameter: 11.2 cm, Thickness: 0.5 cm, Weight: 44.1 gms
Materials: All plastic, 2 sided plastic cursor w/metal tensioniong spring
Scales: 15
Front: K, A, D [ C, CI, B, L]
Back: LL3, LL2, D [ C, S, T1, T2, ST]
Gauge Marks: [ ?, ?’, ?”, ?0, e, C ]