It was a commissioned built by HIWATT
It has been  serviced  6 new JJ KT88 power tubes .

This amp is made with high qualitiy components and attention to detail / build quality is second to none. 
 
can be used 220V /110 V

What Hiwatt.co.uk have to say...

Huge power with pristine clarity delivers your bass lines with conviction without disguising the qualities of the instrument. This amplifier is built to the same spec and uses the schematics of the original dr405. Armed with 6xKT88s, 4xEEC83s and an ECC81 and Partridge designed transformers, this amplifier is versatile as well as powerful. Two normal and two brilliant inputs with volume controls for each, 3 band EQ, presence control and master volume will give you an extensive sonic palette. As with all Custom amps, variable impedance outputs of 4, 8 and 16Ohm are found at the rear along with switchable voltage selectors for those tours abroad. The amps are only built to order.

Dimensions: (Unit alone) 35kg, 705 - 305 - 310 (W x D x H) mm
Shipping Dimensions: (Unit w/case) 46.5kg, 800 - 450 - 400 (W x D x H) mm

It should be noted that while this amp is primarily used by bass players, those “dare to be different” guitarists out there looking for an absolutely crushing tone should check this out! Trust me, your fuzz, OD and distortion pedals NEVER sounded as good as they would in front of this amp!

Some notable users of these amps are: Robert Trujillo (Metallica), Roger Waters & David Gilmour (Pink Floyd) …. enough said, although there are a few more.