Turn and Bank Indicator, 4 Minute Turn, 2.5 inch, PN A1050 Hudson It appears that the lens

It appears that the lens can be removed and the upper and lower operating limit indicators can be set by sliding the triangular pointers along the scale (we have not attempted this in order to preserve the artifact)

It is in nice condition given its age

The liquid has since evaporated

and Grumman TBF Avenger

made by Burton under contract with Bendix Pioneer to the Pioneer Part No

Turn and Bank Indicator, 4 Minute Turn, 2.5 inch, PN A1050 Hudson It appears that the lensThis is a recent era 2. 5 inch, 4 Minute turn, Turn and Bank Indicator made by RC Allen. The glass and case are intact, as is the glass inclinometer. Measures ~5 inches long.