Anybody know wha this is? DEC

Hi, I picked more stuff today and found some DEC hard drives in the pile. Can anyone tell me what size they are and what machines they're for? I *think* they may be out of a Vax, but that's a guess. They're all full height 5 1/4" drives and they weigh a ton. The first one is marked "digital RZ55" and has a sticker that says "1041080-08-9" and it appears to have a SCSI interface. The second one appears to have a ST-506 interface and is a Maxtor drive and is marked "RD54-A" and "30-26245-01" and "RQDX 3". I also picked up a couple of keyboards that I think might be for a DEC. The first one is a large keyboard marked "TS 803". It has 16 Pf keys along the top and a separate numeric keypad. It's gray on top and white on the bottom. The second keyboard is from digital and is a model LK 201. Doe anyone know which machine it's for? Joe