DEC tapes

Hi, I found some more DEC stuff. A bunch of tapes this time. Can anyone tell me what these are for and if they're usefull as they are or should I just use them as scratch tapes for another system. These are original DEC tapes with DEC software. HSC SOFTWARE V3.9 SYS TU58 HSC SOFTWARE V3.9A UTL TU58 HSC SOFTWARE V4.0 UTL TU58 HSC SOFTWARE V4.0 SYS TU58 HSC SOFTWARE V4.1 UTL TU58 HSC SOFTWARE V4.1 SYS TU58 MATNET TIU May 9,1983 MATNET SIMP VER 6.2:6 APRIL 8, 1983 BLANK TU58 (Is this just a blank tape?) Here's a strange one. It appears to be a diagnostics tape but I don't know what system it's for. Can anyone identify it? one tape marked: “C/30 imp+diag 64K” PN 4604263G01 10 64IMP 100 CCT4 300 MEMTEST 400 NIMPTS 500 NIMP4H 600 MTI-UTEST 610 MTI-MTEST 620 MTI-HTEST Thanks, Joe