Md. Code, Agriculture § 11–204.2

(a) Except as provided in subsection (b) of this section, unless registered with the Secretary under § 11-204.3 or § 11-204.4 of this subtitle, a weight and measure may not be used or possessed for current use for:

(1) Buying or selling any commodity or object;

(2) Hire or award;

(3) Computing any charge or payment for services rendered on the basis of weight and measurement; or

(4) Determining any weight and measure for a charge.

(b) This section does not apply to counting scales.