supply of normal single crystal probe , a) subject: procurement of: i) normal single crystal pr probe: zero degree, 2.5 mhz. cry stal size: 20 mm dia. suitable for modsonic makes einstein ii (r) and arya 1 (r). (50 nos.) [ warranty peri od: 30 months after the date of delivery ] ] , ii) normal single crystal probe: zero degree ,1.25 mhz. crystal size: 20 mm dia. suitable for modsonic makes einstein ii (r) and arya 1 (r). (4 nos.) [ warranty period: 30 months after the date of de livery ] ] , iii) low angle perspex wedge attachment for normal single crystal probe angle 17.5 degr ee size 20mm dia (10 nos.) [ warranty period: 30 months after the date of delivery ] ]