An angle indicating instrument which, used in conjunction with a sliding T-Bevel, can indicate to users what miter saw setting to use when cutting two pieces of material for a miter joint, or for cutting one piece of material requiring a miter cut.

An instrument for establishing orientation of a pelvic prosthesis comprises a tripod having an angularly adjustable guide rod on it. The tips of the legs define a plane, and the guide rod is set by the surgeon to a defined orientation with respect to this plane on the basis of preoperative studies. In use, two of the legs of the instrument are positioned by the surgeon at defined anatomical locations on the pelvis (e.g., a point in the region of the posterior/inferior acetabulum and a point on the anterior superior iliac spine). The third leg then lands on the pelvis at a point determined by the position of the first two points, as well as by the separations between the third leg and the other two legs. The position of the guide rod then defines with respect to the actual pelvis the direction for insertion of a prosthesis.

An adapter for a tripodal stereotactic reference frame for use in arthroplastic surgery mounts a third leg of the frame at an angle with respect to the other two legs to facilitate use of said frame with varying surgical exposures.

An adjustable picture frame tool comprising a longitudinal device for housing slidable members at each end wherein the slidable members have the ability to expand and contract in length at both ends of the longitudinal device is disclosed. The longitudinal device and end slidable members each defines a plurality of center spaced holes along their longitudinal axis, respectively. In one preferred embodiment the holes are spaced a mm apart from each other. A clickable circular locking button is located in the middle of the longitudinal device that allows the slidable members to be locked in place to the longitudinal device. In use, a simple click or push of the center button locks the slidable members relative to the longitudinal device wherein a second click of the button and the slidable members can move either outwards or inwards.

A measuring tool for determining angles at two points of interest, including an elongate arm and two protractors, one protractor rotatably mounted at each end of the arm. Each protractor includes a flat for positioning the protractor against one of the two points of interest. The angle at each point of interest is the angular measurement between the arm and the two flats, respectively. The arm may include two attachment sections, one each of the two attachment sections rotatably connected to one each of the two protractors, respectively, and an L-shaped guide having three connection points for selectively receiving and retaining the two attachment sections in various configurations as desired.

A measuring tool for determining angles at two points of interest, including an elongate arm and two protractors, one protractor rotatably mounted at each end of the arm. Each protractor includes a flat for positioning the protractor against one of the two points of interest. The angle at each point of interest is the angular measurement between the arm and the two flats, respectively. The arm may include two attachment sections, one each of the two attachment sections rotatably connected to one each of the two protractors, respectively, and an L-shaped guide having three connection points for selectively receiving and retaining the two attachment sections in various configurations as desired.

An adjustable arch measuring tool measures an arcuate curvature of one of a window and a door and thereby assists a user to layout a radius of the arcuate curvature on an existing cutting surface. The adjustable arch measuring tool includes a first member having an arcuate slot defining an adjustable fulcrum axis formed at a proximal end thereof, a second member having an aperture formed at a proximal end thereof, and a fastener removably inserted through the aperture and selectively locked along a curvilinear longitudinal length of the arcuate slot. Advantageously, the second member is selectively pivoted about the adjustable fulcrum axis defined along the arcuate slot of the first member. With the use of reference points and guide pins, each half of the arch can be easily drawn directly on the working surface.

An educational ruler is a protractor, where the protractor can draw and measure angles. The educational ruler includes a planar disk having a semicircular circumference and labeled in scales along the semicircular circumference; a straight line edge connecting two edges of the semicircular circumference; a through hole on the planar disk; a first edge and a second edge extending from the through hole to the straight line edge; a third edge and a fourth edge extending from the semicircular circumference to the straight line edge. The first edge of the through hole of the educational ruler and the second edge of the through hole of the educational ruler intersect at 90 degrees scale of the planar disk to form the first right angle, and the included angle of the first edge of the through hole of the educational ruler and the straight line edge of the educational ruler is 45 degrees.

An educational ruler is a protractor, where the protractor can draw and measure angles. The educational ruler includes a planar disk having a semicircular circumference and labeled in scales along the semicircular circumference; a straight line edge connecting two edges of the semicircular circumference; a through hole on the planar disk; a first edge and a second edge extending from the through hole to the straight line edge; a third edge and a fourth edge extending from the semicircular circumference to the straight line edge. The first edge of the through hole of the educational ruler and the second edge of the through hole of the educational ruler intersect at 90 degrees scale of the planar disk to form the first right angle, and the included angle of the first edge of the through hole of the educational ruler and the straight line edge of the educational ruler is 45 degrees.

A rafter measuring template includes a length adjustable primary arm, the distance between opposed ends being user-adjustable to indicate a rafter length. A ridge assembly is coupled to the primary arm configured to clamp onto a ridge board and determine potential rafter angle. The ridge assembly includes a clamp portion selectively attachable to the ridge board and securing the primary arm and an angle measurement portion coupled to the clamp portion and pivotal in an up/down manner, the measurement portion having indicia indicative of the angle of the primary arm relative to the ridge board. A wall plate engagement member having a wall plate is coupled to the primary arm defining an upstanding channel having a plurality of spaced apart selectable notches indicative of predetermined rafter widths. A plate engagement flange is capable of nesting flush against the wall plate such that the engagement flange determines a plate notch configuration.