▁the ▁past ▁ 3 ▁years ) ▁in ▁the ▁type ▁of ▁vessel ▁the ▁operator ▁will ▁be ▁handling . ▁ ▁One ▁must ▁also ▁complete ▁a ▁Sa fe ▁Bo ating ▁Cour se ▁( US CG ▁or ▁NA SB LA ▁approved ). ▁ ▁The ▁t onn age ▁of ▁the ▁license ▁is ▁determined ▁by ▁the ▁t onn age ▁of ▁the ▁vessels ▁on ▁which ▁the ▁applic ant ▁declared ▁his / her ▁sea ▁time . ▁ ▁T onn age ▁is ▁granted ▁as ▁either ▁ 2 5 GT , ▁ 5 0 GT ▁or ▁ 1 0 0 GT . ▁ ▁In ▁addition , ▁the ▁license ▁offers ▁an ▁A ux ili ary ▁S ail ▁end ors ement , ▁meaning ▁that ▁if ▁one ▁can ▁demonstrate ▁ 1 2 0 ▁days ▁of ▁service ▁on ▁vessels ▁power ed ▁by ▁sail ▁or ▁auxili ary ▁sail , ▁the ▁license ▁will ▁be ▁extended ▁to ▁allow ▁the ▁license e ▁to ▁operate ▁sail - power ed ▁vessels . ▁ ▁Master , ▁ 1 0 0 ▁T ons ▁Cred ential ▁ ▁The ▁Master , ▁ 1 0 0 ▁Ton ▁License ▁allows ▁the ▁license e ▁to ▁operate ▁Coast ▁Guard ▁ins pected ▁vessels ▁of ▁up ▁to ▁ 1 0 0 GT , ▁granted ▁in ▁ 5 0 GT ▁incre ments . ▁ ▁This ▁license ▁allows ▁the ▁operator ▁to ▁have ▁as ▁many ▁passengers ▁as ▁the ▁ins pected ▁vessel ▁is ▁cert ified ▁to ▁carry ▁( this ▁does ▁not ▁author ize ▁more ▁than ▁six ▁passengers ▁on ▁an ▁un ins pected ▁vessel ). ▁▁ ▁In ▁order ▁to ▁qual ify ▁for ▁a ▁Master , ▁ 1 0