These quality Filter gels are pre-cut & attach quickly & securely to the Honl Photo Speed Strap (sold seperately) & can be used in conjunction with the Honl Snoots, Gobos & Grids (each sold seperately). The usable gel area is 2.5" x 4" & can be trimmed to fit individual strobes (measure the surface area of the front of your strobe to check the fit). The Honl HP-Filter 2 Colour Correction Kit contains two of each of the following filters: 1/2 CTB, Full CTO, 1/2 CTO, 1/4 CTO, Full + Green