Pack II is a powerful flocculant that drops Pack I shocks your pool with a boost of chlorine, helping youįend off bacteria. The HTH Super Green to Blue Advanced Shock is a 2-part system. Imported from USA (Sizes & Specifications are based on the USA Market).YOU'RE ALL CLEAR WITH HTH: For best results, use with HTH 6-Way Test Strips to test and balance your swimming pool water twice weekly.COMPATIBLE WITH ALL SWIMMING POOLS: This product is effective for all pool types that can vacuum to waste It’s ideal for vinyl-lined pools and won't fade liners.VISIBLY BRILLIANT SPARKLE: This Cal Hypo based formula transforms water from green to blue within 24 hours without adding cyanuric acid (CYA) to prevent overstabilization or chlorine lock.EASY TO USE: Simple 2-step system Pack I is a strong algae-fighting pool shock with Cal Hypo Pack II is a powerful flocculant that drops particles to floor for easy vacuuming.BENEFITS: Fight a severe algae bloom and transform your swimming pool water from green to blue in 24 hours with this easy-to-use system.

Hth green to blue shock system