This grower is sure of this plant identification.
Succulent plant for greenhouse, windowsill etc
Lawyer's tongue, Dutch wings
Gasteria genus (Lawyer's tongue). This genus will consists of perennial succulents they are grown for their interesting bell-shaped spiked flowers and dotted lance-shaped leaves which can form a rosette or fan shaped making them useful for the rock garden or containers.
They are frost tender, min 5C, It is easy to grow and will need a sunny position or partial shade in very well drained soil.
Flowers and foliage.