RSS-112 and Ion Chamber Rss-131.  You will need to buy the cable.

High pressurized Ion Chamber

0-100 mR/hr range

7.9 liter ionization chamber

Nearly flat energy response from 0.07 to 10MeV

+/- 5% accuracy at background

HPIC pressure: 25 atmospheres of ultrahigh purity argon

Beta insensitive

Omni directional response

Size: 12″ cube (ion chamber), 17″ X 11″ X 5″ (electronics enclosure)

Weight: 23 lbs. (ion chamber), 25 lbs (electronics enclosure)