152-bit and 256-bit WEP systems are available from some vendors. As with the other WEP variants, 24 bits of that is for the IV, leaving 128 or 232 bits for actual protection. These 128 or 232 bits are typically entered as 32 or 58 hexadecimal characters (4 bits × 32 + 24 bits IV = 152 bits of WEP key, 4 bits × 58 + 24 bits IV = 256 bits of WEP key). Most devices also allow the user to enter it as 16 or 29 ASCII characters (8 bits × 16 + 24 bits IV = 152 bits of WEP key, 8 bits × 29 + 24 bits IV = 256 bits of WEP key).