3M 26141, PPS Series 2.0 Adapter, Type S44, 3/8 Female, 19 Thread BSP, 7100158892 
Insize 4902-6, FRAME LEVELS, 6×6″, 6928640382796
$261.72
Sensitivity .00024in/ft (=0.001?)
V-groove on bottom and left for shafts (shafts diameter .59~2.76″).
With transverse vial.
Supplied with adjusting wrench
Related products
Respirator Cartridges/ Accessories
3M 60379, Eyeglass Frame and Mount 7894/7894-AM, Accessory, with Case, 7000125980
$243.16