Merlin Industries CGOOGLES Goggles for COOL! Holographic Pool Liners - These goggles are for use with COOL! Holographic Pool Liners. COOL! pool liners feature styles that seem regular upon first glance. However, once the compatible COOL! goggles or glasses are worn, the liners showcase a mesmerizing holographic effect. The goggles can be worn for those who prefer the under water experience while glasses can be worn for those who want to enjoy the effect on land. Please note that glasses and holographic liners are sold separately.