From the HM:

Tanabe Racing Development introduces their DF210 & GF210 line of performance lowering springs.

The GF(Grip Feeling) springs are similar to "Sport" style and offer a 30% increase in spring rate and lower the car approx 1.75inches.It's Best to be mated with performance shock upgrades but it can also be used with factory equipment.

The DF(Drop Feeling) springs are similar to "Race" style springs and offer a 15% increase in spring rate and lower the car approx 2.25 inches. For those who want the lowest drop pick these. Both are excellent for daily driving and track use.