sentences:  In 1966 yliluutnantti Juhani Niska submitted a proposal to use modified 100 mm T-54 tank turret as coastal gun.The proposal compared also Swedish 75 mm Bofors turret gun and 76 ItK 31 ss as other possibilities.100 mm T-54 turret was considered the most suitable solution, and after a T-54 turret was tested in Katajaluoto it was decided to purchase 56 T-55 turrets from Soviet Union and modify them as 100 56 TK coastal gun.