INLINE CENTRALIZERS
Centralizers are required for vertical surveys to prevent the tool from spinning. The design of inline centralizers prevents the tool from blocking when surveying open holes as the blades can deform to a minimum diameter of 38 mm.
Polymetra's inline centralizers are designed for the isRG38 running gear. They come with a PVC-tube for transportation and storage. The standard kit consists of:

-2 centralizer bodies with shaft and sliding end
-Bow springs for borehole diameter 3", 4" and 5" (8 each)
-19-mm spanner
-Plastic tube to assist mounting of spring blades