UNIMETRICS CORPORATION

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UNIMETRICS MICROPIPETTER Adjustable delivery to any volume up to rated capacity. Four rated capacities—5MI, 12 /t/1,25 jul. and 50/xl D You select and set any delivery volume within the rated capac­ ity range DAdjustable in less than 10 seconds Your choice of disposable tip styles DTeflon®Tips DMolded Polypropylene Tips One hand operation % No sample contamination DThe sample is wholly con­ tained in the disposable tip. Choice of two models— D Chrome plated aluminum fittings D Glass-filled TPX® fittings

HIGH TORQUE

STIRRERS • Stepless, mechanically adjusted speed regulation 30-350 RPM 350-2600 RPM • No rheostat • Totally enclosed, non-sparking, induction-type motor—115 Volts, 60 Hz • Built-in speed indicator dial • Torque increases with decreasing speed • Flexible positioning • Cast aluminum housing • 2 hollow shafts for rapid stirring rod adjustment to any height • Rods up to r'u" diameter • Complete with chuck and key

Good to the Last Drop i

• Full year warranty Cat. No. 4-741170 RZR-10 STIRRER

Available through most major Lab Supply Dealers

$119.00 Ask for B U L L E T I N 181A offering wide range of stirrers

PolyScience

AC

Corporation

6 3 6 6 GROSS POINT RDAD · NILES

IILINOIS 6 0 6 4 8

(312) 6 4 7 0611

M. here are good reasons for our better accuracy and repro­ ducibility. First, the plunger is carefully hand-honed into the barrel. Second, the accurate external scale is easy to read and providesfor adjustment of the sample size. Third, you draw in a sample excess and then deliver the exact amount of sample without the necessity of "blowing out" the last millismidgen. Any hangup on tip walls is excess-not the sample you require. Fourth, there is a choice of the non-wettable, low friction Tef­ lon tips or the molded polypropylene tips.

Get double the capacity without taking a bath! Consider a laboratory bath f r o m Forma Scient i f i c ' s 2 0 9 5 s e r i e s . C o n s i d e r a 7.5 g a l l o n t a n k capacity, 8 G P M c i r c u l a t i o n , polyurethane in­ sulation, and a new trouble-free stainless steel p u m p . Consider o p t i o n s like direct-dial temper­ ature control, see-through w i n d o w s , proportional r e f r i g e r a t i o n , t h e c o m p l e t e a b s e n c e of r e l a y s o r solenoid valves, and a dual stage pump. T h e n c o n s i d e r F o r m a ' s p r i c e — by far t h e l o w e s t in t h e f i e l d . T h e n d e c i d e . B u y a b a t h — __^,don't t a k e o n e .

Teflon® is a trademark of the Dupont Company. TPX® is a trademark of Imperial Chemical Industries.

Special Introductory Offer ORDER a Unimetrics Micropipetter and receive a vial of T i p s . . . FREE! MODEL: METAL FITTINGS-S60.00/PLASTIC FITTINGS-S48.00 #8010

#8025

#8050

#8100

Rated Delivery Vo1.

5 jul

12μΙ

25 μΙ

50 μ\

Teflon Tips

#2090

#2091

#2092

#2093

Price

$4.50/100 $5.00/100 $5.50/100 $5.50/ 50

Polypropylene Tips Price

#2094

#2094

#2094

US*

P01YCORP

CIRCLE 161 O N READER SERVICE CARD

Because you retain that for Reproducibility and Accuracy of ±1%

CATALOG NO.

Cable

#2094

S4.50/100 $4.50/100 $4.50/100 $4.50/100

May we give you the name of a Unimetrics Dealer in your area? UNIMETRICS CORPORATION 1853 R A Y M O N D A V E . / A N A H Ε I M/CALI F. 9 2 8 0 1 / / 7 1 4 / 879-3777 CIRCLE 192 O N READER SERVICE CARD

114 A • ANALYTICAL CHEMISTRY, VOL. 44, NO. 4, APRIL 1972

Forma Scientific ® BOX 649

.

MARIETTA OHIO 45750

·

AREA CODE 614/373-4763

CIRCLE 6 5 O N READER SERVICE CARD