Sharp Calculator EL-531R Advanced D.A.L. needs new battery

Sharp Scientific Calculator EL-531L Advanced D.A.L.

Sharp EL-531L Scientific Calculator Advanced D.A.L

SHARP Advanced D.A.L.Scientific Calculator w/cover

Sharp Scientific Calculator EL-531R Advanced D.A.L. W/ Cover 5.5"Lx3.5"W

Sharp Advanced DAL Black Handheld Case Scientific Calculator EL-531G Untested

Vintage Sharp Scientific Calculator EL-531S

Sharp EL-531R Advanced D.A.L. Scientific Calculator Clear Blue