This is a NOS, new old stock #5 size machine drip oiler made by Ta Ho Machinery Manufacturing Company in China many years ago.  It has never been used or had oil in it.  It is about 3 1/8 inches in diameter and 6 inches tall overall.  It has 1/4" npt pipe threads that are in great shape.  Everything seems to move and function as it should.  The reservoir cylinder and sight cylinder are both plastic as they should be.  They both are good and this oiler should be ready to be used on your project.  I have two of these oilers and if you buy them both I will include the original Ta Ho shipping box. The pictures tell the story.  If you're looking for a cost effective oiler here it is!  I can be reached at 262 573 193 1 if you'd like to talk about it.  Good Luck.