Hi,
I could not find the tapetype entry for this "not so new" device out
there, so here it is. Seagate STD124000N Scorpion 24 (3,5-in internal).
I have exec. amtapetype several times (the filemark showed "10 kbytes"
once but "0 kbytes" the 3 other times) this is what I recieved:

define tapetype SEAGATE {
    comment "STD124000N"     # Hardware compression off
    length 11567 mbytes
    filemark 0 kbytes                 # The filemark showed "10 kbytes"
once but "0 kbytes" the 3 other times so I guess "0 kbytes" is the right
one to use
    speed 1077 kps
}

\\Reidar