GPT-020F, CLEAR, 50M X 19MM GPT-020F, CLEAR, 50M X 25MM GPT-020F, CLEAR, 50M X 50MM GPT-020F-1000MMX50M GPT-020F-12MMX50M GPT-020F-1540MMX500M GPT-020F-1540MMX50M GPT-020F-19MMX50M GPT-020F-25MMX50M GPT-020F-50MMX50M