Free air or air ttl trigger of your choice add you desired trigger to the basket and use voucher code profotoair at the checkout to apply the saving if you are searching for a wireless self contained off camera flash kit the profoto b1 500 airttl is a premier choice due to popular demand the profto b1 is now available in this twin head kit format offering great value for money and helping you to illuminate your subjects beautifully without being tied to a mains power supply the b1s