The Amaze Amp 5/4 Back Zip stands for an epic stretch without compromising warmth, making it the perfect wetsuit all year round. Freedom of movement in arms and shoulders is key, no matter if you paddle or hold on to your kite or sail. Thus, ION uses a minimal panel design in this area without restricting seams and stretchy I_foam neoprene. Due to its foamy structure, it traps more air. The result is good heat retention. The secret for optimal warmth lies in ION's super flexible Hot_Stuff 2.0 thermo lining throughout the arms & legs combined with toasty warm Plasma_Plush 2.0 in the back. Amaze Amp Backzip models feature additional protection pads at the shins.