The power of attorney and contracts made thereunder may:

(a) Provide for the right of substitution of attorney and revocation of the contract or power.

(b) Impose such restrictions upon the exercise of the power as are agreed upon by the subscribers.

(c) Provide for and limit the maximum amount to be paid by subscribers, except that contracts of exchanges writing either liability or workmen’s compensation insurance shall be subject to the provisions of Article 6 of this chapter.

(d) Provide for the exercise of any right reserved to the subscribers directly or through a board or other body.

(Enacted by Stats. 1935, Ch. 145.)