The Doepfer A-188-1 series are Bucket Brigade Delay modules.  Bucket Brigade delays are known for their warm sound and get grainy as you slow the time down.  An excellent delay for experimental effects and sound design!

There are several models - this is the 1024 stage version, which is capable of short delays but is more useful for flange and Karplus type stuff rather than echoes.  It's hard to specify a maximum delay time as the delay becomes grainier as you slow it down, but it's fastest rates for Karplus should be about 1khz.

All of the Doepfer A-188-1 series feature voltage controlled clock rate (which tracks v/oct for a couple of octaves) Voltage controlled feedback (with exposed feedback path - patch a filter in the feedback path for more mellow string sounds) and Wet/Dry Control.

Specifications:

14Hp

60mm depth

80ma @ +12v

50,a @ -12v