A gradient measurer with 2 scales - rough measure of +/- 35° and fine measure +/- 5°.

Attach to the foreward bulkhead to correct the trim of your boat. No more arguments as to what the boat is doing ;)

Alternatively you can also attach to your camper so you can get a good nights sleep and not fall off your bunk. :

Gradients and inclination are immediately and accurately readable. Fitted with 4 screws or adhesive pad. 10 x 8 cm, 46 g.