Used on the return fuel lines of OM352, OM366 to connect main return line, to smaller head return line. Common to break.
The 8x5x8 is more often found on the 406/416/419 Unimogs.
Double Check your main polyamide fuel line as this T is sold in 2 sizes.
0029901470 = 8MM x 5MM x 8MM
0029901370 = 10MM x 5MM x 10MM