Today I’m running the rule over four FTSE SmallCap (INDEXFTSE: SMX) set to deliver explosive earnings growth.

Market day

Shares in direct marketing specialist 4Imprint Group (LSE: FOUR) have continued to climb to fresh record highs in recent days. And this comes as little surprise to me as organic growth is exploding — the company has seen revenues and orders leap 15% in the first four months of the year.

With huge infrastructure expansion also bolstering the firm’s sales outlook, the City expects earnings at 4Imprint to gallop 27% higher in 2016. And an extra 13% advance is forecast for next year.

Consequently a slightly-toppy P/E rating of 20.6 times for the current period slips to a much-improved 18.6 times for 2017. And I expect the multiple to keep on toppling looking ahead.

Tool up

Tool hire specialist HSS Hire Group (LSE: HSS) has ploughed vast sums into expanding its branch network and hoovering up specialist businesses to bolster its revenues outlook. And these measures are clearly paying off handsomely as HSS printed sales growth of 10% during 2015, outstripping the rental market average of 1.5% by some distance.

The number crunchers expect earnings at HSS to more than double in the current year, resulting in a P/E rating of 17.6 times. And the multiple falls to just 10.6% for 2017 thanks to an anticipated 58% bottom-line improvement.

And a sub-1 PEG reading of 0.2 through to the close of next year underlines HSS’s splendid value for money.

Build bumper returns

I’m convinced Britain’s chronic housing shortage should keep propelling earnings higher at MJ Gleeson (LSE: GLE).

MJ Gleeson saw revenues surge 52.1% during July-December, to £64.8m, helped by solid demand for affordable housing. And the firm plans to expand its geographical reach to help drive the top line still higher.

The City expects MJ Gleeson to enjoy earnings rises of 19% and 11% in the periods to June 2016 and 2017, respectively, resulting in very-decent P/E readings of 13.3 times and 12 times.

And like HSS, PEG readings of 0.7 times for this year and 1.1 times for 2017 at MJ Gleeson indicate unmissable bang for your buck.

Hostel hero

Online hostel-booking specialist Hostelworld Group (LSE: HSW) is in the box seat to enjoy strong revenues expansion, in my opinion, as demand for cheap beds across the globe takes off. Indeed, the company saw bookings leap 21% between July and December last year, and rising success in emerging regions promises to send sales still higher.

Earnings at Hostelworld are set to rise 7% in 2016, according to recent broker forecasts, and an additional 10% advance is chalked-in for 2017.

These figures leave Hostelworld dealing on P/E ratings of just 15.7 times and 13.7 times for these years. I reckon this represents stellar value given the firm’s strong position in a fast-growing sector.

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Royston Wild has no position in any shares mentioned. The Motley Fool UK has no position in any of the shares mentioned. We Fools don't all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors.