A pair of 3" (75mm) caliper points is included with each trammel
Each tram has a knurled swivel grip at the top that turns freely, making it very convenient to swing the tool when scribing circles
Held in place by spring friction, which prevents them from sliding when the nuts are loosened for setting
One tram has a fine-adjusting screw for the points
Rigid, well-designed
The 3" (75mm) points may be adjusted for length in the spring chucks and can be easily replaced with caliper legs or other attachments listed
The ball points with 3" (75mm) holder permit working from holes up to 1-1/2" (38mm) in diameter
The top of the beam is flattened so that when the trams are clamped in position, they will not turn from pressure on the points