スナップオンのロングピンポンチセットになります 5/32" PPC105LA 7/32" PPC107LA 1/4" PPC108LA 5/16" PPC110LA The anvil end on heads of Snap-on punches are machined to a modified parabolic curve This design directs the striking force to the center of the tool to allow slow metal displacement The parabolic curve controls mushrooming to reduce chipping and splitting Heads should be redressed to their original shape with hand files as necessary The tough alloy steel is machined and differentially heat-treated for optimum performance The hardness of the striking head is reduced to help toughness and add qualities that result in a slower mushrooming of the striking surface ということで、ヘッドのマッシュルーム化を防いでいます このポンチの特徴は先端のサイズがインチである事とロングノーズになっていて同じ径が根本まで続きますので対象物に向かって躊躇なく使用できます