Hide legend name in this script, i have so many "Specification #". Need to hide "Specification2 & Specification3 " in this script

Hi Want to hide "Specification2 & Specification3 " legend name only so that i can have "Specification" legend only . I tried but it impacts other legend. Can help?

x=(0.01:2.0)*1e9;
y=-12;
za1= plot(x,y,'-.or');
hold on

x=(2.1:11.1)*1e9;
y1=(-6.68+12.1*log10(x/1e9/5.5));
hold on
za2=plot(x,y1,'-.or');


rfplot(hs1,1,1)
hold on
rfplot(hs2,1,1)
hold on
rfplot(hs3,1,1)
hold on
rfplot(hs4,1,1)
hold on
rfplot(hs5,1,1)
hold on
rfplot(hs6,1,1)
legend('Specification','Specification2','Specification3','Fast,Min V,High T','Fast, Min V,Low T','Slow, Min V,High T','Slow, Min V,Low T','Typical, Min V,High T','Typical, Min V,Low T')