Abstract: To provide for effective force transfer upon striking of blows between plastic end portions covering a metal, typically steel, core without damage to the plastic striking end portions (201, 202), the plastic end portions (201, 202) form part of a single unitary plastic element (200) covering the metal core (100) which, generally, is of ellipsoid shape. The metal core has flat end portions (102, 103), with positioning protrusions (104, 105) extending into matching recesses formed in the striking portions (201, 202) of the plastic covering. The various surfaces of the metal core (102, 103; 106; 107, 108; 109) are joined by inclined surfaces which may be flat or curved and form part of the generally ellipsoid surfaces (110, 111, 112) whereby, upon striking of blows, fissures and breakage of the striking portions are avoided.