Muse Model 2 DAC relpacement fuse

I have an old Muse Model 2 DAC and want to relace the fuse, which is 1/2 amps, 250 volts. As far as I can tell, however, the markings on the fuse caps offer no guidance as to whether the cq replacement should be a slow or fast blo fuse. I'm guessing the former, but would appreciate advice. Unfortunately, I don't have the owner's manual to guide me and I suspect Muse Electronics may have gone belly up (as the phone # on their website now belongs to someone else). Any insights fellow Audigoners can provide would be most welcome. Thanks