Regula 25/51 Mvmt is a a 1 Day Musical Cuckoo Movement with a dancing platform that has a pendulum length of 23.5 cm, a plate size of 73 mm by 73 mm and requires 3 weights of 320 grams each (can be purchased separately). The platform on this movement measures 85 mm high from above the hand shaft. Regula 25/51 Mvmt comes complete with a bird rod, chains, stop rings, weight hooks, hand nuts & an extended post for music activation lever.