{Reposting info from an old thread}
Usually they are called DI, DII, DII or DIV. (Increasing in size and rating)
The ratings of the the different sizes, from small DI to big DIV, are as follows:
DI (maybe 1, 2), 4, 6, 10, 15/16
DII (2, 4), 6, 10, 16, 20, 25A
DIII (32), 35, (40), 50, 63A
DIV 80, 100A.
(Paranthesis indicates special order only)
The DII is the size corresponding to the ordinary E27 light bulb.
Types DII and DIII are very common.
There are also similar looking Neozed fuses, which are a bit more modern and compact.
{Edited to make it more consistent and correct errors}
[This message has been edited by C-H (edited 04-09-2003).]