SCI Systems

(SCI) - Get Report

was down 5% at midday after hitting a 52-week low of $21.69.

Merrill Lynch

downgraded it to intermediate-term neutral from accumulate, its second recent downgrade by the brokerage. Merrill trimmed its earnings estimate for SCI and also cut forecasts for other contract electronics manufacturers.

Affected are

Celestica

(CLS) - Get Report

, down 3.8%;

C-Mac Industries

( EMS), up 1.2%;

Jabil Circuit

(JBL) - Get Report

, down 8.4%;

Sanmina

, down 3.8% and

Solectron

( SLR), down 4%.

Merrill retained its estimate for

Flextronics

(FLEX) - Get Report

, pending the company's conference call.