Undersuit BZ 400 is the warmest one Santi offers. It is designed for diving in water temperature less than 7 degrees Celsius. It is also ideal for long deep diving, with decompression. Best divers and instructors from GUE helped to develop this Undersuit.
Thinsulate BZ 400 insulation is recommended by 3M as optimal for diving undersuits, because it is compressed and do not take too much space under the suit.

It also has a net layer, which make the undersuit even more durable and practically indestructible. The lining is made of soft micropolar 190 gr.

The outside layer is made of Pertex, additionally reinforced with polyester fabric in the areas exposed to damage. In this model we used also good solutions from other versions, like elastic gussets in arms and waist, wide ankle bands and water-resistant cuffs with tapes, which supply air to the dry gloves.

- three pockets
- wide (10 cm) elastic ankle bands
- water-resistant cuffs
- tapes, which supply air to the dry gloves
- banded collar
- two-way zip protected with a flap
- reinforcing patches made of polyester
- elastic gussets in arms;
- in waist - elastic gusset made of the fabric protecting from the wind

Sizing in CM:

SMALL: Height 166-171 / Chest 93-96 / Waist 77-82 / Hips 90-94 / Inside leg 72-74 / Arm length 51 / Trunk 171

MEDIUM: Height 172-177 / Chest 95-100 / Waist 83-88 / Hips 95-99 / Inside leg 75-78 / Arm length 52 / Trunk 175

LARGE: Height 178-183 / Chest 100-105 / Waist 89-94 / Hips 100-105 / Inside leg 79-82 / Arm length 54 / Trunk 179

XLARGE: Height 184-189 / Chest 106-111 / Waist 95-110 / Hips 106-111 / Inside leg 83-86 / Arm length 57 / Trunk 183