DESTU Seal No4 DS4

are designed specifically for the heat Trace range of heating cables and are used as part of the DESTU termination system.
There are 5 seals for the DESTU each seal is specific to a range of cables.
See below:

Heating Cables applicable to DS4

Self-Regulating:
FreezStop Regular FSR-C
FreezStop Extra FSE-C
FreezStop Extra wide FSEw-C
FailSafe Super FSS-C
FreezStop Low Voltage FLVw-C
FailSafe Ultimo FSU-N
FailSafe Ultimo FSUw-N

Constant Wattage: