Notch Trowel 1/4" X 3/8" X 1/4" Sq Notch Box 6. Square notched trowels for spreading mastic, adhesive and thin-set mortars. Trowels are made of hardened tempered steel blade fastened to the aluminum shank with a soft-grip handle. Trowel info: 11" length, 4 1/2" width, soft-grip handle. Notch Trowel 1/4" X 3/8" X 1/4" Sq Notch Box 6.