Not a TriMetric, but for $20 might be worth trying out...
Bayite DC 6.5V-100V Digital ammeter voltmeter Amazon suggested this for me and I'm thinking for $20 I might just give it a try. Has very good reviews too.
Forum Discussion
I have hall effect meters for my dc loads and it does measure "both ways" as when I'm drawing out it reads negative. Limit is 70 amps.
