The Giant series consists of five models based upon two molded cases.
There is a tradeoff between string length and chalk capacity in each of the two cases, so select what is most important to you: string length or chalk capacity.
The 1/8" string in the Giant series is a loose woven polyester. It strikes good lines, and will not deteriorate as quickly as cotton string.
G100: 100 ft of string, 15 oz chalk capacity
G110: 110 ft of string, 12 oz chalk capacity
G130: 130 ft of string, 27 oz chalk capacity
G150: 150 ft of string, 24 oz chalk capacity
G110D: two G110s sharing 110 ft of string. Twice the chalk capacity, and much faster to rechalk the line with one person on each end. Useful when striking a lot of same-length lines repetitively, such as on parking lots.