The modern trend RIS handguard and various scopes have effect to complete elimination of mechanical sights.
But it is not good to rely on the use of a scope with a magnification or battery in the red dots. If to be your weapon still apply, you need sophisticated constructed folding sights. Here you will find the front and back or whole sets style VLTOR, KAC or in the form of modern Magpul MBUS polymer types.
Folding sight for M16, M4, front, D-Boys 13,20 €
Folding sight, MBUS gen.2, black, Magpul PTS 14,00 €
Folding sight, MBUS gen.1, black, Magpul PTS 14,00 €
Folding sights MBUS PRO, black, Magpul PTS 17,20 €
Folding front sight for VLTOR, QD, metal, ACM 19,60 €
Folding sight for M16, M4, rear, D-Boys 12,80 €