Specification heavy duty desk display calculator large 12 digit fixed angle display very large keypad and durable hard keys 4 key memory mark up grand total backspace correction key change sign key rounding amp add mode decimal point selector settings 4 3 2 0 amp floating percentage double zero key square root rubber feet constants addition division multiplication amp subtraction solar powered with battery backup auto power off unit size wxdxh 133 x 198 x 34mm unit weight