Use only on fully cured finishes 6 months or older. Always remove when not in use particularly when applying to nitrocellular based lacquer finishes.
For more information on the suitability of Kling-On guitar products for guitars with various finishes, please see what the manufacturer says about Usage Issues at http://www.kling-on.com/usage_issues.htm.
Most French-Polish finished guitars work very well. Protection for this type of finish was one of the main reasons Kling-On guitar top-protectors were initially developed.
The Kling-On Classical Guitar Top Protector is guaranteed from defects in workmanship and materials for a period of 3 months from the date of purchase.