As per the Alitalia Israel site
Book from 18:00 on 10 May to 8:00 on 11 May, 2017 and fly to Italy and Europe from 18 May, 2017 until 10 July, 2017, last return to Tel Aviv*
USE THE CODE: NIGHT25IL
The 25% discount applies to the all inclusive air fare, on Alitalia flights for departures from Israel to Italy and Europe
This offer is valid to travel from 18 May 2017 until 10 July 2017 (last return to Tel Aviv)
For purchases on alitalia.com the e coupon code can be used exclusively for bookings each with only 1 single adult passenger.
For reservations with more adult passengers is possible to use the discount making separate purchases for single passenger.
If you need to make a booking for adult passengers traveling with children/infants you are kindly requested to contact our Web Assistance at 03-7960766
The 25% discount applies to all inclusive air fares purchased for travel in Economy class only.
The e-Coupon discount code can be used only on the Alitalia Israel website and during the validity period it can be used more than once.
The e-Coupon discount code can also be used for tickets purchased on behalf of other people. The discount can't be used in conjunction with other promotions.
Link
https://www.alitalia.com/en_il/offers/all-offers/night-special.html