4" tapered barrel, stainless, MK II. Interesting that Ruger serializes the barreled receiver rather than the grip frame. I have not seen any aftermarket 'barrels' for them, but I'd be interested to see if they are serialized...
Edit: Bought new, in gray plastic case, w/two magazines and a tiny lock with 4 keys. There is no indication what the lock is intended for (it's not a trigger lock) and it won't lock the plastic case. Nothing else included; no cleaning rod, no bore brush, no 'takedown tool' (it's pretty impossible to pry down the lever in the back of the grip with your fingernail).
I haven't found any way to release the c0cked firing pin. Leaving a fired cartridge in the chamber works but gets you some annoyed looks at the range...
