A graph is maximal knotless if it edge for the property of embedding in $R^3$. We show that such a has at least $\frac74 |V|$ edges, and construct an infinite family graphs with $|E| < \frac52|V|$. With exception = 22$, we any \geq 20$ there exists size $|E|$. classify through nine vertices 20 edges. determine which these maxnik are clique sum smaller not sums.