The requirements for exemption as a professional or administrative employee may be met by an employee who is compensated on a fee basis as well as by one who is paid on a salary basis. Such arrangements are characterized by the payment of an agreed sum for a single job regardless of the time required for its completion. These payments resemble piecework payments with the important distinction that generally speaking a fee payment is made for the kind of job which is unique rather than for a series of jobs which are repeated an indefinite number of times and for which payment on an identical basis is made over and over again. Payments based on the number of hours or days worked and not on the accomplishment of a given single task are not considered payments on a fee basis.
12- 170 C.M.R. ch. 16, § III