diff --git a/htdocs/langs/en_US/products.lang b/htdocs/langs/en_US/products.lang
index d26a645e3c0..9a6efce02b0 100644
--- a/htdocs/langs/en_US/products.lang
+++ b/htdocs/langs/en_US/products.lang
@@ -402,7 +402,7 @@ AmountUsedToUpdateWAP=Amount to use to update the Weighted Average Price
 PMPValue=Weighted average price
 PMPValueShort=WAP
 mandatoryperiod=Mandatory periods
-mandatoryPeriodNeedTobeSet=Warning: Period (start and end date) should be defined
+mandatoryPeriodNeedTobeSet=Note: Period (start and end date) must be defined
 mandatoryPeriodNeedTobeSetMsgValidate=A service requires a start and end period
 mandatoryHelper=Message to the user on the need to enter a start date and an end date on a service when creating / validating an invoice, commercial proposal, sales order. <br> This action is not blocking in the process of confirmation
 DefaultBOM=Default BOM