Baader Planetarium's 2458240 adapter converts the M84 thread on Pentax telescopes to a female M68x1 Zeiss thread. This allows you to use other M68 threaded Baader accessories such as the Ultrashort 2" Eyepiece Clamp (# 2458196) on Pentax OTAs.
Total adapter length = 21.9mm (0.86")
Length of external male thread = 5mm (0.2")
Length of internal female thread = 4mm (0.16")
Maximum outside diameter = 93.6mm (3.69")
Weight = 3.2oz.