From Manufacturer
This Gel Set from Manfrotto includes 12 different gels for use with your Strobo light modification system. The gels slide into the Strobo Gel Holder and allow for many more creative possibilities when shooting with a shoe-mounted flash. Included in this set are warming gels, cooling gels, various colored gels, a 0.6 neutral density gel, and a frosted diffuser gel.
Warming gels of full, 1/2, and 1/4 power CTO are useful for decreasing the color temperature, for example, making a daylight-balanced light work with a tungsten lighting setup
Cooling gels of full, 1/2, and 1/4 power CTB are included for increasing the color temperature of the light
Red, yellow, blue, and green gels are included for creative lighting effects
The 0.6 neutral density gel will decrease the power of your light by two stops
The frosted diffuser gel will soften your light along with decrease its power by a stop