The cobra 2t/4t/8t endcap is a shrink-on sleeve that shrinks under the influence of heat. In cobra systems, it is pulled over the end of the cable and shrunk-on with the help of the cobra blow torch - that gives you a clean end of the cable and a fine point for making the quick splice.
Dimensions: 2t/4t -24 x 50 mm (not shrunk), 8t -39 x 80mm (not shrunk)
Shrinking rate: 1 : 3
Minimum shrinking temperature: +80°C